Terminal apparatus, MME, communication method of terminal apparatus, and communication method of MME

ABSTRACT

To provide a communication procedure for data transmission and/or reception suitable to a CIoT terminal. In a communication control method by a terminal apparatus according to the present invention, a first data transmission and/or reception method is a method for transmitting and/or receiving user data by use of a Signalling Radio Bearer (SRB), a second data transmission and/or reception method is a method for transmitting and/or receiving user data by use of a Data Radio Bearer (DRB), and the communication control method includes a step of changing the user data transmission and/or reception method from the first data transmission and/or reception method into the second data transmission and/or reception method, and a step of transmitting and/or receiving the user data to/from a core network by the second data transmission and/or reception method.

TECHNICAL FIELD

The present invention relates to a terminal apparatus and the like.

This application claims priority based on JP 2016-7687 filed on Jan. 19,2016 in Japan, the contents of which are incorporated herein in itsentirety by reference.

BACKGROUND ART

The 3rd Generation Partnership Project (3GPP), which undertakesactivities for standardizing recent mobile communication systems,discusses System Architecture Enhancement (SAE), which is a systemarchitecture of Long Term Evolution (LTE). 3GPP is in the process ofcreating specifications for the Evolved Packet System (EPS), as acommunication system which realizes an all-IP architecture. Note that acore network constituting the EPS is called the Evolved Packet Core(EPC).

Furthermore, 3GPP recently discusses a Machine to Machine (M2M)communication technology. Note that the M2M communication may bemachine-machine type communication. 3GPP discusses Cellular Internet ofThings (CIoT), in particular, as a technology for supporting Internet ofThings (IoT) in a cellular network of 3GPP.

IoT includes a mobile phone terminal such as a smartphone and refers tovarious IT equipment such as a personal computer and a sensor device,and CIoT extracts technical problems in connecting various terminalapparatuses like these to a cellular network to create specificationsfor solutions to the problems.

For example, it is demanded, in CIoT, to optimize a communicationprocedure for a terminal which needs to increase an efficiency of powerconsumption such that a battery can be maintained for several years, tocope with communication in an indoor or underground state, and toprovide connectivity to a large amount of inexpensively mass-producedterminals. Furthermore, in CIoT, it is demanded to support low data ratecommunication of a simple end node as a requirement.

In this description, a terminal permitted to connect to these 3GPP corenetworks is called a CIoT terminal.

CITATION LIST Non Patent Literature

-   NPL 1: 3rd Generation Partnership Project; Technical Specification    Group Services and System Aspects; Architecture enhancements for    Cellular Internet of Things; (Release 13)

SUMMARY OF INVENTION Technical Problem

In CIoT, discussed is that a function unit having multiple functions isincluded in the core network in order to increase the efficiency of acontrol signal. Specifically, providing a CIoT Serving Gateway Node(C-SGN) responsible for functions of known MME, SGW, and PGW in the corenetwork is discussed.

3GPP discusses that a CIoT terminal is connected to the core networkthrough an access network of CIoT.

Note that the core network to which the CIoT terminal is connected maybe a known core network accommodating a mobile phone terminal such as asmartphone, may be a core network for accommodating a logically dividedCIoT terminal, or may be a core network physically different from theknown core network.

However, a method for connecting to these core networks and a procedurefor data transmission and/or reception to/from these core networks havenot been made clear.

The present invention has been made in view of the above describedsituations, and has an object to provide a communication procedure fordata transmission and/or reception suitable to a CIoT terminal.

Solution to Problem

In order to achieve the above object, a terminal apparatus according tothe present invention includes: a control unit; and a transmissionand/or reception unit, wherein the transmission and/or reception unit isconfigured to perform a communication by use of a control plane CIoT EPSOptimisation, based on completion of an attach procedure, transmit afirst control message to a core network during the communication by useof the control plane CIoT EPS Optimisation, the first control messageincluding a flag for indicating that bearer establishment for thecommunication by use of a user plane CIoT EPS Optimisation is requested,receive a second control message as a response to the first controlmessage from the core network, and perform the communication by use ofthe user plane CIoT EPS Optimisation, based on reception of the secondcontrol message. The transmission and/or reception unit, in the attachprocedure, is configured to transmit an ATTACH REQUEST message to thecore network, receive an ATTACH ACCEPT message from the core network,and transmit an ATTACH COMPLETE message to the core network. The ATTACHREQUEST message includes terminal apparatus capability information forindicating support of the control plane CIoT EPS Optimisation andinformation for indicating a request to use the control plane CIoT EPSOptimisation, and the ATTACH ACCEPT message includes network capabilityinformation for indicating support of the control plane CIoT EPSOptimisation. The control unit receives the network capabilityinformation for indicating the support of the control plane CIoT EPSOptimisation to recognize that use of the communication by use of thecontrol plane CIoT EPS Optimisation is accepted.

A Mobility Management Entity (MME) according to the present inventionincludes: a control unit; and a transmission and/or reception unit,wherein the transmission and/or reception unit is configured to performa communication by use of a control plane CIoT EPS Optimisation, basedon completion of an attach procedure, and in a case that a first controlmessage is received from a terminal apparatus during the communicationby use of the control plane CIoT EPS Optimisation, transmit a secondcontrol message as a response to the first control message to theterminal apparatus. The first control message includes a flag forindicating that bearer establishment for the communication by use of auser plane CIoT EPS Optimisation is requested. The transmission and/orreception unit, in the attach procedure, is configured to receive anATTACH REQUEST message from the terminal apparatus, transmit an ATTACHACCEPT message to the terminal apparatus, and receive an ATTACH COMPLETEmessage from the terminal apparatus. The ATTACH REQUEST message includesterminal apparatus capability information for indicating support of thecontrol plane CIoT EPS Optimisation and information for indicating arequest to use the control plane CIoT EPS Optimisation, and the ATTACHACCEPT message includes network capability information for indicatingsupport of the control plane CIoT EPS Optimisation. The networkcapability information for indicating the support of the control planeCIoT EPS Optimisation is used by the terminal apparatus to recognizethat use of the communication by use of the control plane CIoT EPSOptimisation is accepted, and after the second control message istransmitted, the communication by use of the user plane CIoT EPSOptimisation is performed.

A communication method by a terminal apparatus according to the presentinvention includes the steps of: performing a communication by use of acontrol plane CIoT EPS Optimisation, based on completion of an attachprocedure; transmitting a first control message to a core network duringthe communication by use of the control plane CIoT EPS Optimisation, thefirst control message including a flag for indicating that bearerestablishment for a communication by use of a user plane CIoT EPSOptimisation is requested; receiving a second control message as aresponse to the first control message from the core network; andperforming the communication by use of the user plane CIoT EPSOptimisation, based on reception of the second control message. In theattach procedure, an ATTACH REQUEST message is transmitted to the corenetwork, an ATTACH ACCEPT message is received from the core network, andan ATTACH COMPLETE message is transmitted to the core network. TheATTACH REQUEST message includes terminal apparatus capabilityinformation for indicating support of the control plane CIoT EPSOptimisation and information for indicating a request to use the controlplane CIoT EPS Optimisation, and the ATTACH ACCEPT message includesnetwork capability information for indicating support of the controlplane CIoT EPS Optimisation. By receiving the network capabilityinformation for indicating the support of the control plane CIoT EPSOptimisation, recognized is that use of the communication by use of thecontrol plane CIoT EPS Optimisation is accepted.

A communication method by a Mobility Management Entity (MME) accordingto the present invention includes the steps of: performing acommunication by use of a control plane CIoT EPS Optimisation, based oncompletion of an attach procedure; and in a case that a first controlmessage is received from a terminal apparatus during the communicationby use of the control plane CIoT EPS Optimisation, transmitting a secondcontrol message as a response to the first control message to theterminal apparatus. The first control message includes a flag forindicating that bearer establishment for a communication by use of auser plane CIoT EPS Optimisation is requested. In the attach procedure,an ATTACH REQUEST message is received from the terminal apparatus, anATTACH ACCEPT message is transmitted to the terminal apparatus, and anATTACH COMPLETE message is received from the terminal apparatus. TheATTACH REQUEST message includes terminal apparatus capabilityinformation for indicating support of the control plane CIoT EPSOptimisation and information for indicating a request to use the controlplane CIoT EPS Optimisation, and the ATTACH ACCEPT message includesnetwork capability information for indicating support of the controlplane CIoT EPS Optimisation. The network capability information forindicating the support of the control plane CIoT EPS Optimisation isused by the terminal apparatus to recognize that use of thecommunication by use of the control plane CIoT EPS Optimisation isaccepted, and after the second control message is transmitted, thecommunication by use of the user plane CIoT EPS Optimisation isperformed.

Advantageous Effects of Invention

According to the present invention, a CIoT terminal can attach to and/ordetach from a core network capable of providing multiple transmissionmethods including a user data transmission method optimized for the CIoTterminal to perform communication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating an overview of a mobile communicationsystem.

FIGS. 2A and 2B are diagrams illustrating an example of a configurationof an IP mobile communication network, and the like.

FIGS. 3A and 3B are diagrams illustrating an example of a configurationof an IP mobile communication network, and the like.

FIG. 4 is a diagram illustrating an apparatus configuration of an eNB.

FIG. 5 is a diagram illustrating a second transmission and/or receptionprocedure.

FIG. 6 is a diagram illustrating an apparatus configuration of an MME.

FIG. 7 is a diagram illustrating a storage unit of the MME.

FIG. 8 is a diagram illustrating the storage unit of the MME.

FIG. 9 is a diagram illustrating the storage unit of the MME.

FIG. 10 is a diagram illustrating the storage unit of the MME.

FIG. 11 is a diagram illustrating the storage unit of the MME.

FIG. 12 is a diagram illustrating the storage unit of the MME.

FIG. 13 is a diagram illustrating an apparatus configuration of an SGW.

FIG. 14 is a diagram illustrating a storage unit of the SGW.

FIG. 15 is a diagram illustrating the storage unit of the SGW.

FIG. 16 is a diagram illustrating an apparatus configuration of a PGW.

FIG. 17 is a diagram illustrating a storage unit of the PGW.

FIG. 18 is a diagram illustrating the storage unit of the PGW.

FIG. 19 is a diagram illustrating an apparatus configuration of a C-SGN.

FIG. 20 is a diagram illustrating an apparatus configuration of a UE.

FIG. 21 is a diagram illustrating a storage unit of the UE.

FIG. 22 is a diagram illustrating an outline of a communicationprocedure.

FIG. 23 is a diagram illustrating an attach procedure.

FIG. 24 is a diagram illustrating a PDN connectivity procedure.

FIG. 25 is a diagram illustrating a first transmission and/or receptionmethod change procedure.

FIG. 26 is a diagram illustrating a second transmission and/or receptionmethod change procedure.

FIG. 27 is a diagram illustrating a third transmission and/or receptionmethod change procedure.

FIG. 28 is a diagram illustrating a first transmission and/or receptionprocedure.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a preferred embodiment for carrying out the presentinvention will be described with reference to the drawings. Note that asan example, the present embodiment describes an embodiment of a mobilecommunication system to which the present invention is applied.

1. Embodiment

[1.1. System Overview]

FIG. 1 is a diagram illustrating an overview of a mobile communicationsystem according to the present embodiment. As illustrated in FIG. 1, amobile communication system 1 includes a mobile terminal apparatus UE_A10, an eNB_A 45, a core network_A 90, and a PDN_A 5.

Here, the UE_A 10 may be any wirelessly connectable terminal apparatus,and may be a User equipment (UE), a Mobile equipment (ME), or a MobileStation (MS).

Additionally, the UE_A 10 may be a CIoT terminal. The CIoT terminal isan IoT terminal connectable to the core network A 90, and the IoTterminal includes a mobile phone terminal such a smartphone and may bevarious IT equipment such as a personal computer and a sensor device.

In other words, in a case that the UE_A 10 is the CIoT terminal, theUE_A 10 may request a connection optimized for the CIoT terminal, basedon a policy of the UE_A 10 or a request from the network, or may requestthe known connection. Alternatively, the UE_A 10 may be configured as aterminal apparatus which connects to the core network_A 90 only througha communication procedure optimized for the CIoT terminal beforehandwhen shipping.

Here, the core network_A 90 refers to an IP mobile communication networkrun by a Mobile Operator.

For example, the core network_A 90 may be a core network for the mobileoperator that runs and manages the mobile communication system 1, or maybe a core network for a virtual mobile operator such as a Mobile VirtualNetwork Operator (MVNO). Alternatively, the core network_A 90 may be acore network for accommodating the CIoT terminal.

Additionally, the eNB_A 45 is a base station constituting a radio accessnetwork used by the UE_A 10 to connect to the core network_A 90. Inother words, the UE_A 10 connects to the core network_A 90 using theeNB_A 45.

Additionally, the core network_A 90 is connected to the PDN_A 5. ThePDN_A 5 is a packet data service network which provides a communicationservice to the UE_A 10, and may be configured for each service. Acommunication terminal is connected to the PDN, the UE_A 10 can transmitand/or receive user data to/from the communication terminal located inthe PDN_A 5.

The user data may be data transmitted and/or received between the UE_A10 and devices included in the PDN_A 5. The UE_A 10 transmits the userdata through the core network_A 90 to the PDN_A 5. In other words, theUE_A 10 transmits and/or receives the user data to/from the corenetwork_A 90 in order to transmit and/or receive the user data to/fromthe PDN_A 5. More specifically, the UE_A 10 transmits and/or receivesthe user data to/from a gateway device such as a PGW_A 30 and a C-SGN_A95 in the core network_A 90 in order to transmit and/or receive the userdata to/from the PDN_A 5.

Next, an example of a configuration of the core network_A 90 will bedescribed. In the present embodiment, two configuration examples of thecore network_A 90 will be described.

FIGS. 2A and 2B illustrate an example of the configuration of the corenetwork_90. The core network_A 90 in FIG. 2A includes a Home SubscriberServer (HSS)_A 50, an Authentication, Authorization, Accounting (AAA)_A55, a Policy and Charging Rules Function (PCRF)_A 60, a Packet DataNetwork Gateway (PGW)_A 30, an enhanced Packet Data Gateway (ePDG)_A 65,a Serving Gateway (SGW)_A 35, a Mobility Management Entity (MME)_A 40,and a Serving GPRS Support Node (SGSN)_A 42.

Furthermore, the core network_A 90 is capable of connecting to multipleradio access networks (an LTE AN_A 80, a WLAN ANb 75, a WLAN ANa 70, aUTRAN_A 20, and a GERAN_A 25).

Such a radio access network may be configured to connect to multipledifferent access networks, or may be configured to connect to either oneof the access networks. Moreover, the UE_A 10 is capable of wirelesslyconnecting to the radio access network.

Moreover, a WLAN Access Network b (WLAN ANb 75) that connects to thecore network via the ePDG_A 65 and a WLAN Access Network a (WLAN ANa 75)that connects to the PGW_A, the PCRF_A 60, and the AAA_A 55 can beconfigured as access networks connectable in a WLAN access system.

Note that each apparatus has a configuration similar to those of thedevices of the related art in a mobile communication system using EPS,and thus, detailed descriptions thereof will be omitted. Each apparatuswill be described briefly hereinafter.

The PGW_A 30 is connected to the PDN_A 5, the SGW_A 35, the ePDG_A 65,the WLAN ANa 70, the PCRF_A 60, and the AAA_A 55 and serves as a relaydevice configured to transfer user data by functioning as a gatewaydevice between the PDN_A 5 and the core network_A 90.

The SGW_A 35 is connected to the PGW 30, the MME_A 40, the LTE AN 80,the SGSN_A 42, and the UTRAN_A 20, and serves as a relay deviceconfigured to transfer user data by functioning as a gateway devicebetween the core network_A 90 and the 3GPP access network (the UTRAN_A20, the GERAN_A 25, the LTE AN_A 80).

The MME_A 40 is connected to the SGW_A 35, the LTE AN 80, and the HSS_A50, and serves as an access control device configured to performlocation information management and access control for the UE_A 10 viathe LTE AN 80. Furthermore, the core network_A 90 may include multiplelocation management devices. For example, a location management devicedifferent from the MME_A 40 may be configured. As with the MME_A 40, thelocation management device different from the MME_A 40 may be connectedto the SGW_A 35, the LTE AN 80, and the HSS_A 50.

Furthermore, in a case that multiple MMEs are included in the corenetwork_A 90, the MMEs may be connected to each other. With thisconfiguration, the context of the UE_A 10 may be transmitted and/orreceived between the MMEs.

The HSS_A 50 is connected to the MME_A 40 and the AAA_A 55 and serves asa managing node configured to manage subscriber information. Thesubscriber information of the HSS_A 50 is referred to during MME_A 40access control, for example. Moreover, the HSS_A 50 may be connected tothe location management device different from the MME_A 40.

The AAA_A 55 is connected to the PGW 30, the HSS_A 50, the PCRF_A 60,and the WLAN ANa 70, and is configured to perform access control for theUE_A 10 connected via the WLAN ANa 70.

The PCRF_A 60 is connected to the PGW_A 30, the WLAN ANa 75, the AAA_A55, and the PDN_A 5, and is configured to perform QoS management on datadelivery. For example, the PCRF_A 60 manages QoS of a communication pathbetween the UE_A 10 and the PDN_A 5.

The ePDG_A 65 is connected to the PGW 30 and the WLAN ANb 75 and isconfigured to deliver user data by functioning as a gateway devicebetween the core network_A 90 and the WLAN ANb 75.

The SGSN_A 42 is connected to the UTRAN_A 20, the GERAN_A 25, and theSGW_A 35 and is a control device for location management between a 3G/2Gaccess network (UTRAN/GERAN) and the LTE access network (E-UTRAN). Inaddition, the SGSN_A 42 has functions of: selecting the PGW and the SGW;managing a time zone of the UE; and selecting the MME at the time ofhandover to the E-UTRAN.

Additionally, as illustrated in FIG. 2B, each radio access networkincludes apparatuses to which the UE_A 10 is actually connected (such asa base station apparatus and an access point apparatus), and the like.The apparatuses used in these connections can be thought of asapparatuses adapted to the radio access networks.

In the present embodiment, the LTE AN 80 includes the eNB_A 45. TheeNB_A 45 is a radio base station to which the UE_A 10 connects in an LTEaccess system, and the LTE AN_A 80 may include one or multiple radiobase stations.

The WLAN ANa 70 is configured to include a WLAN APa 72 and a TWAG_A 74.The WLAN APa 72 is a radio base station to which the UE_A 10 connects inthe WLAN access system trusted by the operator running the corenetwork_A 90, and the WLAN ANa 70 may include one or multiple radio basestations. The TWAG_A 74 serves as a gateway device between the corenetwork_A 90 and the WLAN ANa 70. The WLAN APa 72 and the TWAG_A 74 maybe configured as a single device.

Even in a case that the operator running the core network_A 90 and theoperator running the WLAN ANa 70 are different, such a configuration canbe implemented through contracts and agreements between the operators.

Furthermore, the WLAN ANb 75 is configured to include a WLAN APb 76. TheWLAN APb 76 is a radio base station to which the UE_A 10 connects in theWLAN access system in a case that no trusting relationship isestablished with the operator running the core network_A 90, and theWLAN ANb 75 may include one or multiple radio base stations.

In this manner, the WLAN ANb 75 is connected to the core network_A 90via the ePDG_A 65, which is a device included in the core network_A 90,serving as a gateway. The ePDG_A 65 has a security function for ensuringsecurity.

The UTRAN_A 20 is configured to include a Radio Network Controller(RNC)_A 24 and an eNB (UTRAN)_A 22. The eNB (UTRAN)_A 22 is a radio basestation to which the UE_A 10 connects through a UMTS Terrestrial RadioAccess (UTRA), and the UTRAN_A 20 may include one or multiple radio basestations. Furthermore, the RNC_A 24 is a control unit configured toconnect the core network_A 90 and the eNB (UTRAN)_A 22, and the UTRAN_A20 may include one or multiple RNCs. Moreover, the RNC_A 24 may beconnected to one or multiple eNBs (UTRANs)_A 22. In addition, the RNC_A24 may be connected to a radio base station (Base Station Subsystem(BSS)_A 26) included in the GERAN_A 25.

The GERAN_A 25 is configured to include a BSS_A 26. The BSS_A 26 is aradio base station to which the UE_A 10 connects through GSM (tradename)/EDGE Radio Access (GERA), and the GERAN_A 25 may be constituted ofone or multiple radio base station BSSs. Furthermore, the multiple BSSsmay be connected to each other. Moreover, the BSS_A 26 may be connectedto the RNC_A 24.

Next, a second example of a configuration of the core network_A 90 willbe described. For example, in a case that the UE_A 10 is a CIoTterminal, the core network_A 90 may be configured as illustrated inFIGS. 3A and 3B. The core network_A 90 in FIGS. 3A and 3B includes aCIoT Serving Gateway Node (C-SGN)_A 95 and the HSS_A 50. Note that inthe same manner as FIGS. 2A and 2B, in order for the core network_A 90to provide connectivity to an access network other than LTE, the corenetwork_A 90 may include the AAA_A 55 and/or the PCRF_A 60 and/or theePDG_A 65 and/or the SGSN_A 42.

The C-SGN_A 95 may be a node that has some or all of functions of theMME_A 40, the SGW_A 35, and the PGW_A 30 in FIGS. 2A and 2B. The C-SGN_A95 may be a node for managing connectivity establishment ordisconnection, mobility and the like of the CIoT terminal.

In other words, the C-SGN_A 95 may have a gateway device functionbetween the PDN_A and the core network_A 90, a gateway device functionbetween the core network_A 90 and a CIOT AN_A 100, and a locationmanagement function of the UE_A 10.

As illustrated in the figures, the UE_A 10 connects to the corenetwork_A 90 through the radio access network CIOT AN_A 100.

FIG. 3B illustrates the configuration of the CIOT AN_A 100. Asillustrated in the figure, the CIOT AN_A 100 may be configured includingthe eNB_A 45. The eNB_A 45 included in the CIOT AN_A 100 may be the samebase station as the eNB_A 45 included in the LTE AN_A 80. Alternatively,the eNB_A 45 included in the CIOT AN_A 100 may be a base station foraccommodating a CIoT terminal, which is different from the eNB_A 45included in the LTE AN_A 80.

A first core network and/or a second core network may be configured toinclude a system optimized for the IoT.

Note that herein, the UE_A 10 being connected to radio access networksrefers to the UE_A 10 being connected to a base station apparatus, anaccess point, or the like included in each of the radio access networks,and data, signals, and the like being transmitted and/or received alsopass through those base station apparatuses, access points, or the like.

[1.2. Apparatus Configuration]

The configuration of each apparatus will be described below.

[1.2.1. eNB Configuration]

The configuration of the eNB_A 45 will be described below. FIG. 4illustrates an apparatus configuration of the eNB_A 45. As illustratedin FIG. 4, the eNB_A 45 includes a network connection unit_A 420, atransmission and/or reception unit_A 430, a control unit_A 400, and astorage unit_A 440. The network connection unit_A 420, the transmissionand/or reception unit_A 430, and the storage unit_A 440 are connected tothe control unit_A 400 via a bus.

The control unit_A 400 is a function unit for controlling the eNB_A 45.The control unit_A 400 implements various processes by reading out andexecuting various programs stored in the storage unit_A 440.

The network connection unit_A 420 is a function unit through which theeNB_A 45 connects to the MME_A 40 and/or the SGW_A 35 or the C-SGN_A 95.The network connection unit_A 420 is a transmission and/or receptionfunction unit through which the eNB_A 45 transmits and/or receives userdata and/or control data to/from the MME_A 40 and/or the SGW_A 35 or theC-SGN_A 95.

The transmission and/or reception unit_A 430 is a function unit throughwhich the eNB_A 45 connects to the UE_A 10. Furthermore, thetransmission and/or reception unit_A 430 is a transmission and/orreception function unit for transmitting/receiving user data and/orcontrol data to/from the UE_A 10. Furthermore, an external antenna_A 410is connected to the transmission and/or reception unit_A 430.

The storage unit_A 440 is a function unit for storing programs, data,and the like necessary for each operation of the eNB_A 45. A storageunit 640 is constituted of, for example, a semiconductor memory, a HardDisk Drive (HDD), or the like.

The storage unit_A 440 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message which is transmitted and/or received in acommunication procedure described later.

[1.2.2. MME Configuration]

The configuration of the MME_A 40 will be described below. FIG. 6illustrates an apparatus configuration of the MME_A 40. As illustratedin the figure, the MME_A 40 includes a network connection unit_B 620, acontrol unit_B 600, and a storage unit_B 640. The network connectionunit_B 620 and the storage unit_B 640 are connected to the controlunit_B 600 via a bus.

The control unit_B 600 is a function unit for controlling the MME_A 40.The control unit_B 600 implements various processes by reading out andexecuting various programs stored in the storage unit_B 640.

The network connection unit_B 620 is a function unit through which theMME_A 40 connects to the eNB_A 45 and/or the HSS_A 50 and/or the SGW_A35. Moreover, the network connection unit_B 620 is a transmission and/orreception function unit through which the MME_A 40 transmits and/orreceives user data and/or control data to/from the eNB_A 45 and/or theHSS_A 50 and/or the SGW_A 35.

The storage unit_B 640 is a function unit for storing programs, data,and the like necessary for each operation of the MME_A 40. The storageunit_B 640 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_B 640 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message which is transmitted and/or received in acommunication procedure described later.

As illustrated in the figure, the storage unit_B 640 stores an MMEcontext 642, a security context 648, and MME emergency configurationdata 650. Note that the MME context includes an MM context 644 and anEPS bearer context 646. Alternatively, the MME context may include anEMM context and an ESM context. The MM context 644 may be the EMMcontext, and the EPS bearer context 646 may be the ESM context.

FIG. 7, FIG. 8, and FIG. 9 illustrate information elements of the MMEcontext stored for each UE. As illustrated in the figures, the MMEcontext stored for each UE includes an IMSI, anIMSI-unauthenticated-indicator, an MSISDN, an MM State, a GUTI, an MEIdentity, a Tracking Area List, a TAI of last TAU, an E-UTRAN CellGlobal Identity (ECGI), an E-UTRAN Cell Identity Age, a CSG ID, a CSGmembership, an Access mode, an Authentication Vector, a UE Radio AccessCapability, an MS Classmark 2, an MS Classmark 3, Supported Codecs, a UENetwork Capability, an MS Network Capability, UE Specific DRXParameters, a Selected NAS Algorithm, an eKSI, a K_ASME, NAS Keys andCOUNT, a Selected CN operator ID, a Recovery, an Access Restriction, anODB for PS parameters, an APN-OI Replacement, an MME IP address for S11,an MME TEID for S11, an S-GW IP address for S11/S4, an S GW TEID forS11/S4, an SGSN IP address for S3, an SGSN TEID for S3, an eNodeBAddress in Use for S1-MME, an eNB UE S1AP ID, an MME UE S1AP ID, aSubscribed UE-AMBR, a UE-AMBR, EPS Subscribed Charging Characteristics,a Subscribed RFSP Index, an RFSP Index in Use, a Trace reference, aTrace type, a Trigger ID, an OMC identity, a URRP-MME, CSG SubscriptionData, a LIPA Allowed, a Subscribed Periodic RAU/TAU Timer, an MPS CSpriority, an MPS EPS priority, a Voice Support Match Indicator, and aHomogenous Support of IMS Voice over PS Sessions.

The IMSI is permanent identification information of a user. The IMSI isidentical to the IMSI stored in the HSS_A 50.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

The MSISDN represents a phone number of UE. The MSISDN is indicated by astorage unit of the HSS_A 50.

The MM State indicates a Mobility management state of the MME. Thismanagement information indicates an ECM-IDLE state in which a connectionbetween the eNB and the core network is released, an ECM-CONNECTED statein which the connection between the eNB and the core network is notreleased, or an EMM-DEREGISTERED state in which the MME does not storethe location information of the UE.

The Globally Unique Temporary Identity (GUTI) is temporaryidentification information about the UE. The GUTI includes theidentification information about the MME (Globally Unique MME Identifier(GUMMEI)) and the identification information about the UE in a specificMME (M-TMSI).

The ME Identity is an ID of the UE, and may be the IMEI/IMISV, forexample.

The Tracking Area List is a list of tracking area identificationinformation which is assigned to the UE.

The TAI of last TAU is the tracking area identification informationindicated by a recent tracking area update procedure.

The ECGI is cell identification information of the recent UE known bythe MME_A 40.

The E-UTRAN Cell Identity Age indicates the elapsed time since the MMEacquires the ECGI.

The CSG ID is identification information of a Closed Subscriber Group(CSG), in which the UE recently operates, known by the MME.

The CSG membership is member information of the CSG of the recent UEknown by the MME. The CSG membership indicates whether the UE is the CSGmember.

The Access mode is an access mode of a cell identified by the ECGI, maybe identification information indicating that the ECGI is a hybrid whichallows to access both the UEs which is the CSG and is not the CSG.

The Authentication Vector indicates a temporary Authentication and KeyAgreement (AKA) of a specific UE followed by the MME. The AuthenticationVector includes a random value RAND used for authentication, anexpectation response XRES, a key K_ASME, and a language (token) AUTNauthenticated by the network.

The UE Radio Access Capability is identification information indicatinga radio access capability of the UE.

The MS Classmark 2 is a classification symbol (Classmark) of a corenetwork of a CS domain of 3G/2G (UTRAN/GERAN). The MS Classmark 2 isused in a case that the UE supports a Single Radio Voice Call Continuit(SRVCC) for the GERAN or the UTRAN.

The MS Classmark 3 is a classification symbol (Classmark) of a radionetwork of the CS domain of the GERAN. The MS Classmark 3 is used in acase that the UE supports the Single Radio Voice Call Continuit (SRVCC)for the GERAN.

The Supported Codecs are a code list supported by the CS domain. Thislist is used in a case that the UE supports the SRVCC for the GERAN orthe UTRAN.

The UE Network Capability includes an algorithm of security supported bythe UE and a key derivative function.

The MS Network Capability is information including at least one kind ofinformation necessary for the SGSN to the UE having the GERAN and/orUTRAN function.

The UE Specific DRX Parameters are parameters used for determining aDiscontinuous Reception (DRX) cycle length of the UE. Here, the DRX is afunction for changing the UE to a low-power-consumption mode in a casethat there is no communication in a certain period of time, in order toreduce power consumption of a battery of the UE as much as possible.

The Selected NAS Algorithm is a selected security algorithm of aNon-Access Stream (NAS).

The eKSI is a key set indicating the K_ASME. The eKSI may indicatewhether a security key acquired by a security authentication of theUTRAN or the E-UTRAN is used.

The K_ASME is a key for E-UTRAN key hierarchy generated based on aCipher Key (CK) and an Integrity Key (IK).

The NAS Keys and COUNT includes a key K_NASint, a key K_NASenc, and aNAS COUNT parameter. The key K_NASint is a key for encryption betweenthe UE and the MME, the key K_NASenc is a key for security protectionbetween the UE and the MME. Additionally, the NAS COUNT is a count whichstarts a count in a case that a new key by which security between the UEand the MME is established is configured.

The Selected CN operator ID is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The Recovery is identification information indicating whether the HSSperforms database recovery.

The Access Restriction is registration information for accessrestriction.

The ODB for PS parameters indicates a state of an operator determinedbarring (ODB). Here, the ODB is an access rule determined by the networkoperator (operator).

The APN-OI Replacement is a domain name substituting for APN when PGWFQDN is constructed in order to execute a DNS resolution. Thissubstitute domain name is applied to all APNs.

The MME IP address for S11 is an IP address of the MME used for aninterface with the SGW.

The MME TEID for S11 is a Tunnel Endpoint Identifier (TEID) used for theinterface with the SGW.

The S-GW IP address for S11/S4 is an IP address of the SGW used for aninterface between the MME and the SGW or between the SGSN and the MME.

The S GW TEID for S11/S4 is a TEID of the SGW used for the interfacebetween the MME and the SGW or between the SGSN and the MME.

The SGSN IP address for S3 is an IP address of the SGSN used for theinterface between the MME and the SGSN.

The SGSN TEID for S3 is a TEID of the SGSN used for the interfacebetween the MME and the SGSN.

The eNodeB Address in Use for S1-MME is an IP address of the eNBrecently used for an interface between the MME and the eNB.

The eNB UE S1AP ID is identification information of the UE in the eNB.

The MME UE S1AP ID is identification information of the UE in the MME.

The Subscribed UE-AMBR indicates the maximum value of a Maximum Bit Rate(MBR) of uplink communication and downlink communication for sharing allNon-Guaranteed Bit Rate (GBR) bearers (non-guaranteed bearers) inaccordance with user registration information.

The UE-AMBR indicates the maximum value of the MBR of the uplinkcommunication and the downlink communication which are recently used forsharing all the Non-GBR bearers (non-guaranteed bearers).

The EPS Subscribed Charging Characteristics indicate a chargingperformance of the UE. For example, the EPS Subscribed ChargingCharacteristics may indicate registration information such as normal,prepaid, a flat rate, hot billing, or the like.

The Subscribed RFSP Index is an index for a specific RRM configurationin the E-UTRAN acquired from the HSS.

The RFSP Index in Use is an index for the specific RRM configuration inthe E-UTRAN which is recently used.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying an OMCwhich receives the record of the trace.

The URRP-MME is identification information indicating that the HSSrequests UE activity notification from the MME.

The CSG Subscription Data are a relevant list of a PLMN (VPLMN) CSG IDof a roaming destination and an equivalent PLMN of the roamingdestination. The CSG Subscription Data may be associated with anexpiration date indicating an expiration date of the CSG ID and anabsent expiration date indicating that there is no expiration date foreach CSG ID. The CSG ID may be used for a specific PDN connectionthrough LIPA.

The LIPA Allowed indicates whether the UE is allowed to use LIPA in thisPLMN. The Subscribed Periodic RAU/TAU Timer is a timer of a periodic RAUand/or TAU.

The MPS CS priority indicates that the UE is registered in eMLPP or a1×RTT priority service in the CS domain.

The MPS EPS priority is identification information indicating that theUE is registered in MPS in the EPS domain.

The Voice Support Match Indicator indicates whether a radio capabilityof the UE is compatible with the network configuration. For example, theVoice Support Match Indicator indicates whether the SRVCC support by theUE matches the support for voice call by the network.

The Homogenous Support of IMS Voice over PS Sessions for MME isinstruction information indicating, for each UE, whether an IMS voicecall on a PS session is supported. The Homogenous Support of IMS Voiceover PS Sessions for MME includes “Supported” in which an IP MultimediaSubsystem (IMS) voice call on a Packet Switched (PS: line switching)session in all the Tracking Areas (TAs) managed by the MME is supported,and “Not Supported” indicating a case where there is no TA in which theIMS voice call on the PS session is supported. Additionally, the MMEdoes not notify the HSS of this instruction information, in a case thatthe IMS voice call on the PS session is not uniformly supported (the TAin which the support is performed and the TA in which the support is notperformed are both present in the MME), and in a case that it is notclear whether to be supported.

FIG. 10 illustrates information elements included in the MME context foreach PDN connection stored for each PDN connection. As illustrated inthe figure, the MME context for each PDN connection includes an APN inUse, an APN Restriction, an APN Subscribed, a PDN Type, an IP Address,EPS PDN Charging Characteristics, an APN-OI Replacement, SIPTOpermissions, a Local Home Network ID, LIPA permissions, a WLANoffloadability, a VPLMN Address Allowed, a PDN GW Address in Use(control information), a PDN GW TEID for S5/S8 (control information), anMS Info Change Reporting Action, a CSG Information Reporting Action, aPresence Reporting Area Action, an EPS subscribed QoS profile, aSubscribed APN-AMBR, an APN-AMBR, a PDN GW GRE Key for uplink traffic(user data), a Default bearer, and a low access priority.

The APN in Use indicates an APN which is recently used. This APNincludes identification information about the APN network andidentification information about a default operator.

The APN Restriction indicates a restriction on a combination of an APNtype to an APN associated with this bearer context. In other words, theAPN Restriction is information for restricting the number of APNs whichcan be established and the APN type.

The APN Subscribed refers to a registration APN received from the HS S.

The PDN Type indicates the type of the IP address. The PDN Typeindicates IPv4, IPv6, or IPv4v6, for example.

The IP Address indicates an IPv4 address or an IPv6 Prefix. Note thatthe IP address may store both the IPv4 and IPv6 prefixes.

The EPS PDN Charging Characteristics indicate a charging performance.The EPS PDN Charging Characteristics may indicate, for example, normal,prepaid, a flat rate, or hot billing.

The APN-OI Replacement is a proxy domain name of APN having the samerole as that of the APN-OI Replacement, registered for each UE. Notethat the APN-OI Replacement has a higher priority than that of theAPN-OI Replacement for each UE.

The SIPTO permissions indicate permission information to a Selected IPTraffic Offload (SIPTO) of traffic using this APN. Specifically, theSIPTO permissions identify a prohibition of the use of SIPTO, permissionof the use of SIPTO in the network excluding the local network,permission of the use of SIPTO in the network including the localnetwork, or permission of the use of SIPTO only in the local network.

The Local Home Network ID indicates identification information of a homenetwork to which the base station belongs, in a case that SIPTO(SIPTO@LN) using the local network can be used.

The LIPA permissions are identification information indicating whetherthis PDN can access through LIPA. Specifically, the LIPA permissions maybe an LIPA-prohibited which does not permit LIPA, an LIPA-only whichpermits only LIPA, or an LIPA-conditional which permits LIPA dependingon a condition.

The WLAN offload ability is identification information indicatingwhether traffic connected through this APN can perform offload to thewireless LAN by utilizing a cooperative function between the wirelessLAN and 3GPP, or maintains the 3GPP connection. The WLAN offload abilitymay vary for each RAT type. Specifically, different WLAN offloadabilities may be present for LTE (E-UTRA) and 3G (UTRA).

The VPLMN Address Allowed indicates whether a connection in which the UEuses this APN is allowed to use only an HPLMN domain (IP address) PGW inPLMN (VPLMN) of the roaming destination or allowed to use additionallythe PGW in the VPLMN domain. The PDN GW Address in Use (controlinformation) is an IP address of the PGW used recently. This address isused when a control signal is transmitted.

The PDN GW TEID for S5/S8 (control information) is a TEID used fortransmission and/or reception of the control information in an interface(S5/S8) between the SGW and the PGW.

The MS Info Change Reporting Action is an information element indicatingthat it is necessary to notify the PGW of user location informationbeing changed.

The CSG Information Reporting Action is an information elementindicating that it is necessary to notify the PGW of CSG informationbeing changed.

The Presence Reporting Area Action indicates necessity of notificationof the change as to whether the UE is present in a Presence ReportingArea. This information element separates into identification informationof the presence reporting area and an element included in the presencereporting area.

The EPS subscribed QoS profile indicates a QoS parameter to a DefaultBearer at a bearer level.

The Subscribed APN-AMBR indicates the maximum value of the Maximum BitRate (MBR) of the uplink communication and the downlink communicationfor sharing all the Non-GBR bearers (non-guaranteed bearers) establishedfor this APN in accordance with the user registration information.

The APN-AMBR indicates the maximum value of the Maximum Bit Rate (MBR)of the uplink communication and the downlink communication for sharingall the Non-GBR bearers (non-guaranteed bearers) established for thisAPN, which has been determined by the PGW.

The PDN GW GRE Key for uplink traffic (user data) is a Generic RoutingEncapsulation (GRE) key for the uplink communication of the user data inan interface between the SGW and the PGW.

The Default Bearer is EPS bearer identification information, which isinformation acquired and/or generated in establishing a PDN connection,for identifying the Default Bearer associated with the PDN connection.

The EPS bearer in the present embodiment may be a communication pathestablished between the UE_A 10 and the C-SGN_A 95. Furthermore, the EPSbearer may include a Radio Bearer (RB) established between the UE_A 10and the eNB_A 45, and an S1 bearer established between the eNB_A 45 andthe C-SGN_A 95. Here, the RB and the EPS bearer may be associated witheach other on a one-to-one basis. Therefore, identification informationof the RB may be associated with the identification information of theEPS bearer on a one-to-one basis, or may be the same identificationinformation as of the EPS bearer.

The EPS bearer may be a logical communication path established betweenthe UE_A 10 and the PGW_A 30. In this case also, the EPS bearer may beconfigured to include the Radio Bearer (RB) established between the UE_A10 and the eNB_A 45. Furthermore, the RB and the EPS bearer may beassociated with each other on a one-to-one basis. Therefore,identification information of the RB may be associated with theidentification information of the EPS bearer on a one-to-one basis, ormay be the same identification information as of the EPS bearer.

Therefore, the Default Bearer may be identification informationidentifying a Signalling Radio Bearer (SRB) and/or a Control SignallingRadio Bearer (CRB), or identification information identifying a DataRadio Bearer (DRB).

Here, the SRB in the present embodiment may be originally an RBestablished for transmitting and/or receiving the control informationsuch as the control message. Here, the CRB in the present embodiment maybe originally an RB established for transmitting and/or receiving thecontrol information such as the control message. In the presentembodiment, the RB for originally transmitting and/or receiving thecontrol message is used to transmit and/or receive the user data.Therefore, the present embodiment uses the SRB or the CRB to transmitand/or receive the control message and the user data.

The DRB in the present embodiment may be an RB established fortransmitting and/or receiving the user data.

The low access priority indicates that the UE requests a low accesspriority, when the PDN connection is opened.

FIG. 11 illustrates the MME context stored for each bearer. Asillustrated in the figure, the MME context stored for each bearerincludes an EPS Bearer ID, a TI, an S-GW IP address for S1-u, an S-GWTEID for S1u, a PDN GW TEID for S5/S8, a PDN GW IP address for S5/S8, anEPS bearer QoS, and a TFT.

The EPS Bearer ID is the only identification information for identifyingthe EPS bearer for a UE connection via the E-UTRAN.

Note that the EPS Bearer ID may be EPS bearer identification informationidentifying a dedicated bearer. Therefore, the EPS bearer ID may beidentification information identifying the EPS bearer different from theDefault Bearer.

As already described above, the EPS bearer may be a communication pathestablished between the UE_A 10 and the C-SGN_A 95. Furthermore, the EPSbearer may include a Radio Bearer (RB) established between the UE_A 10and the eNB_A 45, and an S1 bearer established between the eNB_A 45 andthe C-SGN_A 95. Here, the RB and the EPS bearer may be associated witheach other on a one-to-one basis. Therefore, identification informationof the RB may be associated with the identification information of theEPS bearer on a one-to-one basis, or may be the same identificationinformation as of the EPS bearer.

The EPS bearer may be a logical communication path established betweenthe UE_A 10 and the PGW_A 30. In this case also, the EPS bearer may beconfigured to include the Radio Bearer (RB) established between the UE_A10 and the eNB_A 45. Furthermore, the RB and the EPS bearer may beassociated with each other on a one-to-one basis. Therefore,identification information of the RB may be associated with theidentification information of the EPS bearer on a one-to-one basis, ormay be the same identification information as of the EPS bearer.

Therefore, the EPS bearer ID identifying the dedicated bearer may beidentification information identifying a Signalling Radio Bearer (SRB)and/or a Control Signalling Radio Bearer (CRB), or identificationinformation identifying a Data Radio Bearer (DRB).

Here, as already described above, the SRB in the present embodiment maybe originally an RB established for transmitting and/or receiving thecontrol information such as the control message. Here, the CRB in thepresent embodiment may be originally an RB established for transmittingand/or receiving the control information such as the control message. Inthe present embodiment, the RB for originally transmitting and/orreceiving the control message is used to transmit and/or receive theuser data. Therefore, the present embodiment uses the SRB or the CRB totransmit and/or receive the control message and the user data.

The DRB in the present embodiment may be an RB established fortransmitting and/or receiving the user data.

The TI is an abbreviation of a “Transaction Identifier”, and isidentification information identifying a bidirectional message flow(Transaction).

The S-GW IP address for S1-u is an IP address of the SGW used for aninterface between the eNB and the SGW.

In a case that the user data is transmitted and/or received with beingincluded in the message for control information, the S-GW IP address forS1-u may be an IP address of the SGW used for the interface between theMME and/or the SGSN and the SGW, or may be the S-GW IP address forS11/S4.

The S-GW TEID for S1u is a TEID of the SGW used for the interfacebetween the eNB and the SGW.

In a case that the MME and/or the user data is transmitted and/orreceived with being included in the message for control information, theS-GW TEID for S1u may be a TEID address of the SGW used for theinterface between the SGSN and the SGW, or may be the S-GW TEID forS11/S4.

The PDN GW TEID for S5/S8 is a TEID of the PGW for user datatransmission in the interface between the SGW and the PGW.

The PDN GW IP address for S5/S8 is an IP address of the PGW for userdata transmission in the interface between the SGW and the PGW.

The EPS bearer QoS includes a QoS Class Identifier (QCI) and anAllocation and Retention Priority (ARP). QCI indicates a class to whichthe QoS belongs. QoS can be classified in accordance with presence orabsence of band control, an allowable delay time, a packet loss rate, orthe like. The QCI includes information indicating the priority. ARP isinformation representing a priority relating to maintaining the bearer.

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer.

Here, the information elements included in the MME context illustratedin FIG. 7 to FIG. 11 are included in either the MM context 644 or theEPS bearer context 646. For example, the MME context for each bearerillustrated in FIG. 11 may be stored in the EPS bearer context, and theother information elements may be stored in the MM context.Alternatively, the MME context for each PDN connection illustrated inFIG. 10 and the MME context for each bearer illustrated in FIG. 11 maybe stored in the EPS bearer context, and the other information elementsmay be stored in the MM context.

As illustrated in FIG. 6, the storage unit_B 640 of the MME may storethe security context 648. FIG. 12(e) illustrates information elementsincluded in the security context 648.

As illustrated in the figure, the security context includes an EPS ASsecurity context and an EPS NAS security context. The EPS AS securitycontext is a context relating to security of an access stratum (AccessStream (AS)), the EPS NAS security context is a context relating tosecurity of a non-access stratum (Non-Access Stream (NAS)).

FIG. 12(f) illustrates information elements included in the EPS ASsecurity context. As illustrated in the figure, the EPS AS securitycontext includes a cryptographic key, a Next Hop parameter (NH), a NextHop Chaining Counter parameter (NCC), and identifiers of the selected ASlevel cryptographic algorithms.

The cryptographic key is an encryption key in an access stratum.

The NH is an information element determined from the K_ASME. The NH isan information element for enabling a forward security.

The NCC is an information element associated with the NH. The NCCrepresents the number of occurrences of handovers in a verticaldirection changing the network.

The identifiers of the selected AS level cryptographic algorithms areidentification information of a selected encryption algorithm.

FIG. 12(g) illustrates information elements included in the EPS NASsecurity context. As illustrated in the figure, the EPS NAS securitycontext may include the K_ASME, a UE Security capabilitie, and the NASCOUNT.

The K_ASME is a key for E-UTRAN key hierarchy generated based on thekeys CK and IK.

The UE Security capabilitie is a set of identification informationcorresponding to a cipher and an algorithm used by the UE. Thisinformation includes information for the access stratum and informationfor the non-access stratum. Furthermore, in a case that the UE supportsaccess to the UTRAN/GERAN, this information includes information for theUTRAN/GERAN.

The NAS COUN is a counter indicating the time during which the K_ASME isoperating.

The security context 648 may be included in the MME context 642.Additionally, as illustrated in FIG. 6, the security context 648 and theMME context 642 may be separately present.

FIG. 12(h) illustrates information elements stored in the MME emergencyconfiguration data 650. The MME emergency configuration data isinformation which is used instead of registration information of the UEacquired from the HSS. As illustrated in the figure, the MME emergencyconfiguration data 650 includes an Emergency Access Point Name (em APN),an Emergency QoS profile, an Emergency APN-AMBR, an Emergency PDN GWidentity, and a Non-3GPP HO Emergency PDN GW identity.

The em APN indicates an access point name used for the PDN connectionfor emergency.

The Emergency QoS profile indicates QoS of the Default Bearer of em APNat a bearer level.

The Emergency APN-AMBR indicates the maximum value of the MBR of theuplink communication and the downlink communication for sharing theNon-GBR bearers (non-guaranteed bearers) established for em APN. Thisvalue is determined by the PGW.

The Emergency PDN GW identity is identification information of the PGWstatically configured on the em APN. This identification information maybe an FQDN or an IP address.

The Non-3GPP HO Emergency PDN GW identity is identification informationof the PGW statically configured on the em APN, in a case that the PLMNsupports a handover to an access network other than 3GPP. Thisidentification information may be an FQDN or an IP address.

Furthermore, the MME_A 40 may manage a connection state with respect tothe UE while synchronizing with the UE.

[1.2.3. SGW Configuration]

Hereinafter, the configuration of the SGW_A 35 will be described. FIG.13 illustrates an apparatus configuration of the SGW_A 35. Asillustrated in the figure, the SGW_A 35 includes a network connectionunit_C 1320, a control unit_C 1300, and a storage unit_C 1340. Thenetwork connection unit_C 1320 and the storage unit_C 1340 are connectedto the control unit_C 1300 via a bus.

The control unit_C 1300 is a function unit for controlling the SGW_A 35.The control unit_C 1300 implements various processes by reading out andexecuting various programs stored in the storage unit_C 1340.

The network connection unit_C 1320 is a function unit through which theSGW_A 35 connects to the eNB_A 45 and/or the MME_A 40 and/or the PGW_A30 and/or SGSN_A 42. The network connection unit_C 1320 is atransmission and/or reception function unit through which the SGW_A 35transmits and/or receives user data and/or control data to/from theeNB_A 45 and/or the MME_A 40 and/or the PGW_A 30 and/or SGSN_A 42.

The storage unit_C 1340 is a function unit for storing programs, data,and the like necessary for each operation of the SGW_A 35. The storageunit_C 1340 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_C 1340 may store at least identification informationand/or control information and/or a flag and/or a parameter included inthe control message transmitted and/or received in a communicationprocedure described.

As illustrated in the figure, the storage unit_C 1340 stores an EPSbearer context 1342. Note that the EPS bearer context includes an EPSbearer context stored for each UE, an EPS bearer context stored for eachPDN, and an EPS bearer context stored for each bearer.

FIG. 14 illustrates information elements of the EPS bearer contextstored for each UE. As illustrated in FIG. 14, the EPS bearer contextstored for each UE includes an IMSI, an MSI-unauthenticated-indicator,an ME Identity, an MSISDN, a Selected CN operator id, an MME TEID forS11, an MME IP address for S11, an S-GW TEID for S11/S4, an S-GW IPaddress for S11/S4, an SGSN IP address for S4, an SGSN TEID for S4, aTrace reference, a Trace type, a Trigger ID, an OMC identity, a Lastknown Cell Id, and a Last known Cell Id age.

The IMSI is permanent identification information of a user. The IMSI isidentical to the IMSI in the HSS_A 50.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

The ME Identity is identification information of the UE, and may be theIMEI/IMISV, for example.

The MSISDN represents a basic phone number of the UE. The MSISDN isindicated by a storage unit of the HSS_A 50.

The Selected CN operator id is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The MME TEID for S11 is a TEID of the MME used for the interface betweenthe MME and the SGW.

The MME IP address for S11 is an IP address of the MME used for theinterface between the MME and the SGW.

The S-GW TEID for S11/S4 is a TEID of the SGW used for the interfacebetween the MME and the SGW, or the interface between the SGSN and theSGW.

The S-GW IP address for S11/S4 is an IP address of the SGW used for theinterface between the MME and the SGW, or the interface between the SGSNand the SGW.

The SGSN IP address for S4 is an IP address of the SGSN used for theinterface between the SGSN and the SGW.

The SGSN TEID for S4 is a TEID of the SGSN used for the interfacebetween the SGSN and the SGW.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace Type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying an OMCwhich receives the record of the trace.

The Last known Cell ID is recent location information of the UE notifiedby the network.

The Last known Cell ID age is information indicating the period from thetime when the Last known Cell ID is stored to the present.

Furthermore, the EPS bearer context includes an EPS bearer context foreach PDN connection stored for each PDN connection. FIG. 15(c)illustrates the EPS bearer context for each PDN connection. Asillustrated in the figure, the EPS bearer context for each PDNconnection includes an APN in Use, EPS PDN Charging Characteristics, aP-GW Address in Use (control information), a P-GW TEID for S5/S8(control information), a P-GW Address in Use (user data), a P-GW GRE Keyfor uplink (user data), an S-GW IP address for S5/S8 (controlinformation), an S-GW TEID for S5/S8 (control information), an S-GWAddress in Use (user data), a S-GW GRE Key for downlink traffic (userdata), and a Default Bearer.

The APN in Use indicates an APN which is recently used. This APNincludes identification information about the APN network andidentification information about a default operator. Additionally, thisinformation is information acquired from the MME or the SGSN.

The EPS PDN Charging Characteristics indicate a charging performance.The EPS PDN Charging Characteristics may indicate, for example, normal,prepaid, a flat rate, or hot billing.

The P-GW Address in Use (control information) is an IP address of thePGW used when the SGW recently transmits the control information.

The P-GW TEID for S5/S8 (control information) is a TEID of the PGW usedfor transmission of the control information in the interface between theSGW and the PGW.

The P-GW Address in Use (user data) is an IP address of the PGW usedwhen the SGW recently transmits the user data.

The P-GW GRE Key for uplink (user data) is the GRE key for the uplinkcommunication of the user data in the interface between the SGW and thePGW.

The S-GW IP address for S5/S8 (control information) is an IP address ofthe SGW used for the interface of the control information between theSGW and the PGW.

The S-GW TEID for S5/S8 (control information) is a TEID of the SGW usedfor the interface of the control information between the GW and the PGW.

The S GW Address in Use (user data) is an IP address of the SGW which isrecently used when the SGW transmits the user data.

The S-GW GRE Key for downlink traffic (user data) is the GRE key of theuplink communication used for the interface of the user data between theSGW and the PGW.

The Default Bearer is identification information, which is informationacquired and/or generated in establishing a PDN connection, foridentifying the Default Bearer associated with the PDN connection.

Furthermore, the EPS bearer context of the SGW includes the EPS bearercontext for each bearer. FIG. 15(d) illustrates the EPS bearer contextfor each bearer. As illustrated in the figure, the EPS bearer contextfor each bearer includes an EPS Bearer Id, a TFT, a P-GW Address in Use(user data), a P-GW TEID for S5/S8 (user data), an S-GW IP address forS5/S8 (user data), an S-GW TEID for S5/S8 (user data), an S-GW IPaddress for S1-u, S12 and S4 (user data), an S-GW TEID for S1-u, S12 andS4 (user data), an eNodeB IP address for S1-u, an eNodeB TEID for S1-u,an RNC IP address for S12, an RNC TEID for S12, an SGSN IP address forS4 (user data), an SGSN TEID for S4 (user data), an EPS Bearer QoS, anda Charging Id.

The EPS Bearer Id is the only identification information identifying theEPS bearer for the UE connection via the E-UTRAN. That is, the EPSBearer Id is identification information for identifying the bearer. Inother words, the EPS Bearer Id is identification information of the EPSbearer. Moreover, the EPS Bearer Id may be identification informationidentifying the SRB and/or the CRB, or identification informationidentifying the DRB.

The TFT indicates all the packet filters associated with the EPS bearer.In other words, the TFT is information identifying some pieces of thetransmitted and/or received user data, and thus, the SGW_A 35 uses theEPS bearer associated with the TFT to transmit and/or receive the userdata identified by the TFT. Further in other words, the SGW_A 35 usesthe EPS bearer which includes the RB associated with the TFT to transmitand/or receive the user data identified by the TFT.

The SGW_A 35 may use the Default Bearer to transmit and/or receive theuser data which cannot be identified by the TFT.

The SGW_A 35 may store in advance the TFT associated with the DefaultBearer.

The P-GW Address in Use (user data) is an IP address of the PGW which isrecently used for transmission of the user data in the interface betweenthe SGW and the PGW.

The P-GW TEID for S5/S8 (user data) is a TEID of the PGW for theinterface of the user data between the SGW and the PGW.

The S-GW IP address for S5/S8 (user data) is an IP address of the SGWfor the user data received from the PGW.

The S-GW TEID for S5/S8 (user data) is a TEID of the SGW for theinterface of the user data between the SGW and the PGW.

The S-GW IP address for S1-u, S12 and S4 (user data) is an IP address ofthe SGW used for the interface between the SGW and the 3GPP accessnetwork (the LTE access network or GERAN/UTRAN).

In the case that the user data is transmitted and/or received with beingincluded in the message for control information, the S-GW IP address forS1-u, S12 and S4 (user data) may be an IP address of the SGW used forthe interface between the SGW and the MME and/or the SGSN, or may be theS-GW IP address for S11/S4.

The S-GW TEID for S1-u, S12 and S4 (user data) is a TEID of the SGW usedfor the interface between the SGW and the 3GPP access network (the LTEaccess network or GERAN/UTRAN).

In the case that the user data is transmitted and/or received with beingincluded in the message for control information, the S-GW TEID for S1-u,S12 and S4 (user data) may be a TEID of the SGW used for the interfacebetween the SGW and the MME and/or the SGSN, or may be the S-GW TEID forS11/S4.

The eNodeB IP address for S1-u is an IP address of the eNB used fortransmission between the SGW and the eNB.

In the case that the user data is transmitted and/or received with beingincluded in the message for control information, the eNodeB IP addressfor S1-u may be an IP address of the MME used for the interface betweenthe MME and the SGW, or may be the MME IP address for S11.

The eNodeB TEID for S1-u is a TEID of the eNB used for the transmissionbetween the SGW and the eNB.

In the case that the user data is transmitted and/or received with beingincluded in the message for control information, the eNodeB TEID forS1-u may be a TEID of the MME used for the interface between the MME andthe SGW, or may be the MME TEID for S11.

The RNC IP address for S12 is an IP address of the RNC used for aninterface between the SGW and the UTRAN.

The RNC TEID for S12 is a TEID of the RNC used for the interface betweenthe SGW and the UTRAN.

The SGSN IP address for S4 (user data) is an IP address of the SGSN usedfor transmission of the user data between the SGW and the SGSN.

The SGSN TEID for S4 (user data) is a TEID of the SGSN used for thetransmission of the user data between the SGW and the SGSN.

The EPS Bearer QoS represents the QoS of this bearer, and may include anARP, a GBR, an MBR, and a QCI. Here, the ARP is information representingthe priority relating to maintaining the bearer. Additionally, theGuaranteed Bit Rate (GBR) represents a band guaranteed bit rate, and theMaximum Bit Rate (MBR) represents the maximum bit rate. The QCI can beclassified in accordance with presence or absence of band control, anallowable delay time, a packet loss rate, or the like. The QCI includesinformation indicating the priority.

The Charging Id is identification information for recording charginggenerated in the SGW and the PGW.

[1.2.4. PGW Configuration]

Hereinafter, the configuration of the PGW_A 30 will be described. FIG.16 illustrates an apparatus configuration of the PGW_A 30. Asillustrated in the figure, the PGW_A 30 includes a network connectionunit_D 1620, a control unit_D 1600, and a storage unit_D 1640. Thenetwork connection unit_D 1620 and the storage unit_D 1640 are connectedto the control unit_D 1600 via a bus.

The control unit_D 1600 is a function unit for controlling the PGW_A 30.The control unit_D 1600 implements various processes by reading out andexecuting various programs stored in the storage unit_D 1640.

The network connection unit_D 1620 is a function unit through which thePGW_A 30 is connected to the SGW_A 35 and/or the PCRF_A 60 and/or theePDG_A 65 and/or the AAA_A 55 and/or the TWAG_A 74 and/or the PDN_A 5.The network connection unit_D 1620 is a transmission and/or receptionfunction unit through which the PGW_A 30 transmits and/or receives userdata and/or control data to/from the SGW_A 35 and/or the PCRF_A 60and/or the ePDG_A 65 and/or the AAA_A 55 and/or the TWAG_A 74 and/or thePDN_A 5.

The storage unit_D 1640 is a function unit for storing programs, data,and the like necessary for each operation of the PGW_A 30. The storageunit_D 1640 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_D 1640 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message which is transmitted and/or received in acommunication procedure described later.

As illustrated in the figure, the storage unit_D 1640 stores an EPSbearer context 1642. Note that the EPS bearer context includes an EPSbearer context stored for each UE, an EPS bearer context stored for eachAPN, an EPS bearer context stored for each PDN connection, and an EPSbearer context stored for each bearer which may be separately stored inthe EPS bearer context.

FIG. 17(b) illustrates information elements included in the EPS bearercontext stored for each UE. As illustrated in the figure, the EPS bearercontext stored for each UE includes an IMSI, anIMSI-unauthenticated-indicator, an ME Identity, an MSISDN, a Selected CNoperator id, a RAT type, a Trace reference, a Trace type, a Trigger id,and an OMC identity.

The IMSI is identification information to be assigned to a user usingthe UE.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

The ME Identity is an ID of the UE, and may be the IMEI/IMISV, forexample.

The MSISDN represents a basic phone number of the UE. The MSISDN isindicated by a storage unit of the HSS_A 50.

The Selected CN operator ID is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The RAT type indicates a recent Radio Access Technology (RAT) of the UE.The RAT type may be, for example, the E-UTRA (LTE), the UTRA, or thelike.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying an OMCwhich receives the record of the trace.

Next, FIG. 17(c) illustrates the EPS bearer context stored for each APN.As illustrated in the figure, the EPS bearer context stored for each APNof the PGW storage unit includes an APN in use and an APN-AMBR.

The APN in Use indicates an APN which is recently used. This APNincludes identification information about the APN network andidentification information about a default operator. This information isacquired from the SGW.

The APN-AMBR indicates the maximum value of the Maximum Bit Rate (MBR)of the uplink communication and the downlink communication for sharingall the Non-GBR bearers (non-guaranteed bearers) established for thisAPN.

Furthermore, FIG. 18(d) illustrates the EPS bearer context for each PDNconnection stored for each PDN connection. As illustrated in the figure,the EPS bearer context for each PDN connection includes an IP Address, aPDN type, an S-GW Address in Use (control information), an S-GW TEID forS5/S8 (control information), an S-GW Address in Use (user data), an S-GWGRE Key for downlink traffic (user data), a P-GW IP address for S5/S8(control information), a P-GW TEID for S5/S8 (control information), aP-GW Address in Use (user data), a P-GW GRE Key for uplink traffic (userdata), an MS Info Change Reporting support indication, an MS Info ChangeReporting Action, a CSG Information Reporting Action, a PresenceReporting Area Action, a BCM, a Default Bearer, and EPS PDN ChargingCharacteristics.

The IP Address indicates an IP address assigned to the UE for this PDNconnection. The IP address may be an IPv4 and/or IPv6 prefix.

The PDN type indicates the type of the IP address. The PDN typeindicates IPv4, IPv6, or IPv4v6, for example.

The S-GW Address in Use (control information) is an IP address of theSGW which is recently used for transmission of the control information.

The S-GW TEID for S5/S8 (control information) is a TEID of the SGW usedfor transmission and/or reception of the control information between theSGW and the PGW.

The S-GW Address in Use (user data) is an IP address of the SGW which isrecently used for transmission of the user data in the interface betweenthe SGW and the PGW.

The S-GW GRE Key for downlink traffic (user data) is the GRE key whichis assigned to be used in the downlink communication of the user datafrom the PGW to the SGW in the interface between the SGW and the PGW.

The P-GW IP address for S5/S8 (control information) is an IP address ofthe PGW used for communication of the control information.

The P-GW TEID for S5/S8 (control information) is a TEID of the PGW forcommunication of the control information which uses the interfacebetween the SGW and the PGW.

The P-GW Address in Use (user data) is an IP address of the PGW which isrecently used for transmission of the user data which uses the interfacebetween the SGW and the PGW.

The P-GW GRE Key for uplink traffic (user data) is the GRE key which isassigned for the uplink communication of the user data between the SGWand the PGW, that is, transmission of the user data from the SGW to thePGW.

The MS Info Change Reporting support indication indicates that the MMEand/or the SGSN supports a notification process of user locationinformation and/or user CSG information.

The MS Info Change Reporting Action is information indicating whetherthe MME and/or the SGSN is requested to transmit a change in the userlocation information.

The CSG Information Reporting Action is information indicating whetherthe MME and/or the SGSN is requested to transmit a change in the userCSG information. This information is separately indicated (a) for a CSGcell, (b) for a hybrid cell in which a user is a CSG member, (c) for ahybrid cell in which the user is not the CSG member, or for acombination thereof.

The Presence Reporting Area Action indicates necessity of notificationof the change as to whether the UE is present in a Presence ReportingArea. This information element separates into identification informationof the presence reporting area and an element included in the presencereporting area.

The Bearer Control Mode (BCM) indicates a control state of a bearernegotiated with respect to the GERAN/UTRAN.

The Default Bearer is EPS bearer identification information, which isinformation acquired and/or generated in establishing a PDN connection,for identifying the Default Bearer associated with the PDN connection.

The EPS PDN Charging Characteristics are a charging performance. Thecharging performance may indicate, for example, normal, prepaid, a flatrate, hot billing.

Furthermore, FIG. 18(e) illustrates the EPS bearer context stored foreach EPS bearer. As illustrated in the figure, the EPS bearer contextincludes an EPS Bearer Id, a TFT, an S-GW Address in Use (user data), anS-GW TEID for S5/S8 (user data), a P-GW IP address for S5/S8 (userdata), a P-GW TEID for S5/S8 (user data), an EPS Bearer QoS, and aCharging Id.

The EPS Bearer Id is identification information identifying the accessof the UE via the E-UTRAN. In other words, the EPS Bearer Id isidentification information of the EPS bearer. Moreover, the EPS BearerId may be identification information identifying the SRB and/or the CRB,or identification information identifying the DRB.

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer. In other words, theTFT is information identifying some pieces of the transmitted and/orreceived user data, and thus, the PGW_A 30 uses the EPS bearerassociated with the TFT to transmit and/or receive the user dataidentified by the TFT. Further in other words, the PGW_A 30 uses the EPSbearer which includes the RB associated with the TFT to transmit and/orreceive the user data identified by the TFT.

The PGW_A 30 may use the Default Bearer to transmit and/or receive theuser data which cannot be identified by the TFT.

The PGW_A 30 may store in advance the TFT associated with the DefaultBearer.

The S-GW Address in Use (user data) is an IP address of the SGW which isrecently used for transmission of the user data.

The S-GW TEID for S5/S8 (user data) is a TEID of the SGW forcommunication of the user data which uses the interface between the SGWand the PGW.

The P-GW IP address for S5/S8 (user data) is an IP address of the PGWfor the user data received from the PGW.

The P-GW TEID for S5/S8 (user data) is a TEID of the PGW forcommunication of the user data between the SGW and the PGW.

The EPS Bearer QoS indicates the QoS of the bearer, and may include anARP, a GBR, an MBR, and a QCI. Here, the ARP is information representingthe priority relating to maintaining the bearer. Additionally, theGuaranteed Bit Rate (GBR) represents a band guaranteed bit rate, and theMaximum Bit Rate (MBR) represents the maximum bit rate. The QCI can beclassified in accordance with presence or absence of band control, anallowable delay time, a packet loss rate, or the like. The QCI includesinformation indicating the priority.

The Charging Id is charging identification information for identifyingthe record relating to charging generated in the SGW and the PGW.

[1.2.5. C-SGN Configuration]

Hereinafter, an apparatus configuration of the C-SGN_A 95 will bedescribed. FIG. 19 illustrates the apparatus configuration of theC-SGN_A 95. As illustrated in the figure, the C-SGN_A 95 includes anetwork connection unit_E 1920, a control unit_E 1900, and a storageunit_E 1940. The network connection unit_E 1920 and the storage unit_E1940 are connected to the control unit_E 1900 via a bus.

The control unit_E 1900 is a function unit for controlling the C-SGN_A95. The control unit_E 1900 implements various processes by reading outand executing various programs stored in the storage unit_E 1940.

The network connection unit_E 1920 is a function unit through which theC-SGN_A 95 connects to the eNB_A 45 and/or the HSS_A 50 and/or the PDN_A5. The network connection unit_E 1920 is a transmission and/or receptionfunction unit through which the C-SGN_A 95 transmits and/or receivesuser data and/or control data to/from the eNB_A 45 and/or the HSS_A 50and/or the PDN_A 5.

The storage unit_E 1940 is a function unit for storing programs, data,and the like necessary for each operation of the C-SGN_A 95. The storageunit_E 1940 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_E 1940 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message which is transmitted and/or received in acommunication procedure described later.

The storage unit_E 1940 stores a context A 1942, a context B 1944, acontext C 1946, and a context D 1948 as illustrated in the figure.

The context A 1942 may be the MME context 642 illustrated in FIG. 6.Additionally, the context B 1944 may be the security context 648illustrated in FIG. 6. Additionally, the context C 1946 may be the MMEemergency configuration data 650 illustrated in FIG. 6.

Additionally, the context D 1948 may be the EPS bearer context 1342illustrated in FIG. 13. Additionally, the context E 1950 may be the EPSbearer context 1642 illustrated in FIG. 16.

Note that in a case that the context A 1942 to the context E 1950include the same information element, such information element may notnecessarily be redundantly stored in the storage unit_E 1940, and may bestored in any context at least.

Specifically, for example, the IMSI may be included in each of thecontext A 1942, the context D 1948, and the context E 1950, or may bestored in any context.

The storage unit_E 1940 may include the TFT.

Here, the TFT is an abbreviation of a “Traffic Flow Template”, andindicates all packet filters associated with the EPS bearer. In otherwords, the TFT is information identifying some pieces of the transmittedand/or received user data, and thus, the C-SGN_A 95 uses the EPS bearerassociated with the TFT to transmit and/or receive the user dataidentified by the TFT. Further in other words, the C-SGN_A 95 uses theEPS bearer which includes the RB associated with the TFT to transmitand/or receive the user data identified by the TFT.

The C-SGN_A 95 may use the Default Bearer to transmit and/or receive theuser data which cannot be identified by the TFT.

The C-SGN_A 95 may store in advance the TFT associated with the DefaultBearer.

[1.2.6. UE Configuration]

FIG. 20 illustrates an apparatus configuration of the UE_A 10. Asillustrated in the figure, the UE_A 10 includes a transmission and/orreception unit_F 2020, a control unit_F 2000, and a storage unit_F 2040.The transmission and/or reception unit_F 2020 and the storage unit_F2040 are connected to the control unit_F 2000 via a bus.

The control unit_F 2000 is a function unit for controlling the UE_A 10.The control unit_F 2000 implements various processes by reading out andexecuting various programs stored in the storage unit_F 2040.

The transmission and/or reception unit_F 2020 is a function unit throughwhich the UE_A 10 connects to an IP access network via an LTE basestation. Furthermore, an external antenna_F 2010 is connected to thetransmission and/or reception unit_F 2020.

In other words, the transmission and/or reception unit_F 2020 is afunction unit through which the UE_A 10 connects to the eNB_A 45.Furthermore, the transmission and/or reception unit_F 2020 is atransmission and/or reception function unit through which the UE_A 10transmits and/or receives user data and/or control data to/from theeNB_A 45.

The storage unit_F 2040 is a function unit for storing programs, data,and the like necessary for each operation of the UE_A 10. The storageunit_F 2040 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_F 2040 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message which is transmitted and/or received in acommunication procedure described later.

As illustrated in the figure, the storage unit_F 2040 stores a UEcontext 2042. Hereinafter, information elements stored in the storageunit_F 2040 will be described.

FIG. 20 illustrates information elements included in the UE contextstored for each UE. As illustrated in the figure, the UE context storedfor each UE includes an IMSI, an EMM State, a GUTI, an ME Identity, aTracking Area List, a last visited TAI, a Selected NAS Algorithm, aSelected AS Algorithm, an eKSI, K_ASME, NAS Keys and COUNT, a TIN, UESpecific DRX Parameters, an Allowed CSG list, and an Operator CSG list.

The IMSI is permanent identification information of a subscriber.

The EMM State indicates a mobility management state of the UE. Forexample, the EMM State may be EMM-REGISTERED in which the UE isregistered with the network (registered state) or EMM-DEREGISTERD inwhich the UE is not registered with the network (deregistered state).

The GUTI is an abbreviation of “Globally Unique Temporary Identity,” andis temporary identification information on the UE. The GUTI includes theidentification information about the MME (Globally Unique MME Identifier(GUMMEI)) and the identification information about the UE in a specificMME (M-TMSI).

The ME Identity is an ID of an ME, and may be the IMEI/IMISV, forexample.

The Tracking Area List is a list of the tracking area identificationinformation which is assigned to the UE.

The last visited TAI is the tracking area identification informationincluded in the Tracking Area List, and is identification information ofthe latest tracking area that the UE visits.

The Selected NAS Algorithm is a selected security algorithm of the NAS.

The Selected AS Algorithm is a selected security algorithm of the AS.

The eKSI is a key set indicating the K_ASME. The eKSI may indicatewhether a security key acquired by a security authentication of theUTRAN or the E-UTRAN is used.

The K_ASME is a key for E-UTRAN key hierarchy generated based on thekeys CK and IK.

The NAS Keys and COUNT includes a key K_NASint, a key K_NASenc, and aNAS COUNT. The K_NASint is a key for encryption between the UE and theMME, the K_NASenc is a key for safety protection between the UE and theMME. Additionally, the NAS COUNT is a count which starts a count in acase that a new key by which security between the UE and the MME isestablished is configured.

The Temporary Identity used in Next update (TIN) is temporaryidentification information used in the UE in an attach procedure or alocation information update procedure (RAU/TAU).

The UE Specific DRX Parameters are a Discontinuous Reception (DRX) cyclelength of the selected UE.

The Allowed CSG list is a list of the PLMN associated with a CSG ID of amember to which the allowed UE belongs, under the control of both theuser and the operator.

The Operator CSG list is a list of the PLMN associated with the CSG IDof a member to which the allowed UE belongs, under the control of onlythe operator.

Next, FIG. 21(c) illustrates the UE context for each PDN connectionstored for each PDN connection. As illustrated in the figure, the UEcontext for each PDN connection includes an APN in Use, an APN-AMBR, anAssigned PDN Type, an IP Address, a Default Bearer, and a WLANoffloadability.

The APN in Use is an APN which is recently used. This APN may includeidentification information about the network and identificationinformation about a default operator.

The APN-AMBR indicates the maximum value of the MBR of the uplinkcommunication and the downlink communication for sharing the Non-GBRbearers (non-guaranteed bearers). The APN-AMBR is established for eachAPN.

The Assigned PDN Type is a type of the PDN assigned from the network.The Assigned PDN Type may be IPv4, IPv6, or IPv4v6, for example.

The IP Address is an IP address assigned to the UE, and may be an IPv4address or an IPv6 prefix.

The Default Bearer is EPS bearer identification information, which isinformation acquired from the core network_A 90 in establishing a PDNconnection, for identifying the Default Bearer associated with the PDNconnection.

The WLAN offloadability is WLAN offload permission informationindicating whether to allow for offload to the WLAN by using aninterworking function between the WLAN and the 3GPP, or to maintain the3GPP access.

FIG. 21(d) illustrates the UE context for each bearer stored in thestorage unit of the UE. As illustrated in the figure, the UE context foreach bearer includes an EPS Bearer ID, a TI, an EPS bearer QoS, and aTFT.

The EPS Bearer ID is identification information of the EPS bearer. TheEPS Bearer ID may be identification information identifying the SRBand/or the CRB, or identification information identifying the DRB.

The TI is an abbreviation of a “Transaction Identifier”, and isidentification information identifying a bidirectional message flow(Transaction).

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer. In other words, theTFT is information identifying some pieces of the transmitted and/orreceived user data, and thus, the UE_A 10 uses the EPS bearer associatedwith the TFT to transmit and/or receive the user data identified by theTFT. Further in other words, the UE_A 10 uses the RB associated with theTFT to transmit and/or receive the user data identified by the TFT.

The UE_A 10 may use the Default Bearer to transmit and/or receive theuser data which cannot be identified by the TFT.

The UE_A 10 may store in advance the TFT associated with the DefaultBearer.

[1.3. Description of Communication Procedure]

Next, a communication procedure according to the present embodiment willbe described with reference to FIG. 22.

The communication procedure according to the present embodiment firstperforms an attach procedure (S2200) as illustrated in FIG. 22. The UE_A10 and/or the eNB_A 45 and/or the C-SGN_A 95 may determine a datatransmission and/or reception method in the attach procedure (S2200). Aspecific data transmission and/or reception method may be transmissionand/or reception based on any procedure of a first transmission and/orreception procedure, a second transmission and/or reception procedure,or a third transmission and/or reception procedure.

Next, a PDN connectivity procedure (S2202) may be performed depending ona condition described later.

Next, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may performa first data transmission and/or reception (S2204) based on thetransmission and/or reception method determined in the attach procedure.

Next, a transmission and/or reception method change procedure (S2206)may be performed. The UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95may modify the data transmission and/or reception method in thetransmission and/or reception method change procedure.

Next, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may performa second data transmission and/or reception (S2208) based on thetransmission and/or reception method determined in the transmissionand/or reception method change procedure.

In the following, a description is give of the conditions under whichthe procedures are performed and details of the processes.

Here, the first transmission and/or reception procedure is a procedurein which the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 transmitand/or receive the user data via connectionless communication withoutestablishing the DRB.

In other words, the first transmission and/or reception procedure may bea procedure to transmit the user data by use of the SRB and/or the CRBfor transmitting and/or receiving the control message.

Here, the second transmission and/or reception procedure is a procedurein which the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 in anidle mode in the present embodiment transmit and/or receive the userdata.

To be more specific, the second transmission and/or reception procedureis a procedure in which the UE_A 10 and/or the eNB_A 45 and/or theC-SGN_A 95 enter an active mode from the idle mode in the presentembodiment, and thereafter, transmit and/or receive the user data by useof the established DRB.

Furthermore, the second transmission and/or reception procedure may be aprocedure including a procedure in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 enter the idle mode in the present embodiment fromthe active mode after the completion of the transmission and/orreception of the user data.

The idle mode in the present embodiment is a mode for releasing an RBresource, but may be a mode indicating that the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 continue to keep the context for the DRB and/orDefault Bearer.

Here, the third transmission and/or reception procedure is a procedurein which the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 in anidle mode of related art transmit and/or receive the user data.

To be more specific, the third transmission and/or reception procedureis a procedure in which the UE_A 10 and/or the eNB_A 45 and/or theC-SGN_A 95 enter the active mode from the idle mode of related art, andthereafter, transmit and/or receive the user data by use of theestablished DRB.

Furthermore, the third transmission and/or reception procedure may be aprocedure including a procedure in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 enter the idle mode of related art from the activemode after the completion of the transmission and/or reception of theuser data.

In other words, the third transmission and/or reception procedure may bea user data transmission and/or reception procedure of related art.

The idle mode of related art may be a mode for releasing an RB resourceand indicating that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 discard the context for the DRB and/or Default Bearer. In the presentembodiment, such an idle mode is expressed as the idle mode of relatedart in order to distinguish from the idle mode in the present embodimentdescribe above.

A detailed description of each transmission and/or reception procedureis described later.

Here, before describing the detailed steps of the procedures, in orderto avoid redundant descriptions, terms specific to the presentembodiment and primary identification information used in the procedureswill be described beforehand.

The connectionless communication in the present embodiment may becommunication performing at least a process in which the UE_A 10transmits the Non-Access Stream (NAS) message including the data packetto the eNB_A 45, by including the NAS message in the Radio ResourceControl (RRC) message. And/or, the connectionless communication may becommunication for transmitting and/or receiving the data packet betweenthe UE_A 10 and the eNB_A 45 without establishing the RRC connection.And/or, the connectionless communication may be communication that theUE_A 10 in the idle state transmits and/or receives the data packet.Further in other words, the connectionless communication may becommunication for transmitting and/or receiving the user data by use ofthe SRB or the CRB.

The active mode in the present embodiment may be a mode indicating astate that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 cantransmit and/or receive the user data with establishing the DRB and/orthe Default Bearer and/or the PDN connection.

The DRB in the present embodiment may be a communication pathestablished for transmission and/or reception of the user data, such asa radio bearer.

The PDN connection in the present embodiment may be a connectionestablished between the UE_A 10 and the C-SGN_A 95 for transmissionand/or reception of the user data.

The idle mode in the present embodiment and/or the idle mode of relatedart may be a mode indicating a state that the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 cannot transmit and/or receive the user datawith releasing the DRB and/or the Default Bearer resource.

An attach complete state in the present embodiment is a state ofconnecting to the network with authentication being provided. This staterefers to a state that the user data can be transmitted and/or receivedbetween the UE_A 10 and the PDN_A 5.

To be more specific, the attach complete state may be a state that theUE_A 10 and/or the PDN_A 5 and/or the eNB_A 45 and/or the C-SGN_A 95 cantransmit and/or receive the user data.

The attach complete state may include a first mode, a second mode, athird mode, a fourth mode, and a fifth mode described below. Therespective modes are distinguishable according to whether or not the PDNconnection is established, and/or a difference in the data transmissionand/or reception method, and/or a difference in the stored informationwhen entering the idle mode, and the like, and detailed descriptions ofthe modes are given below.

Here, the first mode may be a mode in which the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 establish the PDN connection.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 establish the Default Bearer.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the dedicated bearer.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 can transmit and/or receive the userdata.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 connectionlessly transmit and/or receivethe user data.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data without establishing theRRC connection.

And/or, the first mode may be a mode in which the UE_A 10 and/or theC-SGN_A 95 transmit and/or receive the user data with being included inthe NAS message.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data with being included inthe RRC message.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive a NAS Packet Data Unit (PDU) with beingincluded in the RRC message. The NAS PDU may be a control messageobtained by including the user data in the NAS message.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data by use of the SRB.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data by use of the CRB.

The SRB and the CRB may be a communication path used for transmissionand/or reception of the control message, such as a radio bearer.

And/or, the first mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user data byuse of the bearer used for transmission and/or reception of the controlinformation.

In the case of the first mode, the UE_A 10 and/or the eNB_A 45 and/orthe C-SGN_A 95 may transmit and/or receive the user data by use of thefirst transmission and/or reception procedure.

And/or, in the case of the first mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt a method for transmitting and/orreceiving the user data by use of the first transmission and/orreception procedure as an initial transmission and/or reception method.

And/or, in the case of the first mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt the EPS bearer including the SRB and/orthe CRB as the Default Bearer.

The Default Bearer may be a first bearer, or a bearer for transmittingand/or receiving the user data in the initial transmission and/orreception method.

Here, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the PDN connection.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the Default Bearer.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the dedicated bearer.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 cannot transmit and/or receive the userdata.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 determine to connectionlessly transmitand/or receive the user data.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data withoutestablishing the RRC connection.

And/or, the second mode may be a mode in which the UE_A 10 and/or theC-SGN_A 95 determine to transmit and/or receive the user data with beingincluded in the NAS message.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data with beingincluded in the RRC message.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive a NAS Packet Data Unit(PDU) with being included in the RRC message. The NAS PDU may be acontrol message obtained by including the user data in the NAS message.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data by use ofthe SRB.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data by use ofthe CRB.

The SRB and the CRB may be a communication path used for transmissionand/or reception of the control message, such as a radio bearer.

And/or, the second mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 determine to transmit and/or receive theuser data by use of the bearer used for transmission and/or reception ofthe control information.

In the case of the second mode, the UE_A 10 and/or the eNB_A 45 and/orthe C-SGN_A 95 may determine to transmit and/or receive the user data byuse of the first transmission and/or reception procedure.

And/or, in the case of the second mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may determine to adopt a method for transmittingand/or receiving the user data by use of the first transmission and/orreception procedure as the initial transmission and/or reception method.

And/or, in the case of the second mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may determine to adopt the EPS bearer includingthe SRB and/or the CRB as the Default Bearer.

The Default Bearer may be the first bearer, or the bearer fortransmitting and/or receiving the user data in the initial transmissionand/or reception method.

Here, the third mode may be a mode in which the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 establish the PDN connection.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 continue to keep the context in a casethat the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 enter theidle mode.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 establish the Default Bearer.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the dedicated bearer.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 can transmit and/or receive the userdata.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user data byuse of the established connection.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data with establishing the RRCconnection.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data by use of the DRB.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user datawith establishing the bearer for transmitting and/or receiving the userdata.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 continue to keep the context even in thecase that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 enterthe idle mode.

And/or, the third mode may be a mode in which the UE_A 10 and/or theeNB_A 45 can transmit and/or receive a third message of the RRCincluding the NAS message.

In the case of the third mode, the UE_A 10 and/or the eNB_A 45 and/orthe C-SGN_A 95 may transmit and/or receive the user data by use of thesecond transmission and/or reception procedure.

And/or, in the case of the third mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt a method for transmitting and/orreceiving the user data by use of the second transmission and/orreception procedure as the initial transmission and/or reception method.

And/or, in the case of the third mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt the EPS bearer including the DRB as theDefault Bearer.

The Default Bearer may be the first bearer, or the bearer fortransmitting and/or receiving the user data in the initial transmissionand/or reception method.

The PDN connection having been established at the time of entering thethird mode may enter the idle mode in the present embodiment dependingon a condition such as that no user data is transmitted and/or received.

Here, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the PDN connection.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the Default Bearer.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 do not establish the dedicated bearer.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 cannot transmit and/or receive the userdata.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 determine to transmit and/or receive theuser data with establishing the RRC connection.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data withestablishing the RRC connection.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to transmit and/or receive the user data by use ofthe DRB.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 determine to transmit and/or receive theuser data with establishing the bearer for transmitting and/or receivingthe user data.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 determine to continue to keep the contexteven in the case that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 enter the idle mode.

And/or, the fourth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 determine to be able to transmit and/or receive the thirdmessage of the RRC including the NAS message.

In the case of the fourth mode, the UE_A 10 and/or the eNB_A 45 and/orthe C-SGN_A 95 may determine to transmit and/or receive the user data byuse of the second transmission and/or reception procedure.

And/or, in the case of the fourth mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may determine to adopt a method for transmittingand/or receiving the user data by use of the second transmission and/orreception procedure as the initial transmission and/or reception method.

And/or, in the case of the fourth mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may determine to adopt the EPS bearer includingthe DRB as the Default Bearer.

The Default Bearer may be the first bearer, or the bearer fortransmitting and/or receiving the user data in the initial transmissionand/or reception method.

Here, the fifth mode may be a mode in which the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 establish the PDN connection.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 establish the Default Bearer.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 can transmit and/or receive the userdata.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 transmit and/or receive the user data by use of the DRB.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user datawith establishing the bearer for transmitting and/or receiving the userdata.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user datawith establishing the Default Bearer.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user datawith establishing two or more bearers.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 and/or the C-SGN_A 95 discard the context when the UE_A 10and/or the eNB_A 45 and/or the C-SGN_A 95 enter the idle mode.

And/or, the fifth mode may be a mode in which the UE_A 10 and/or theeNB_A 45 cannot transmit and/or receive the third message of the RRCincluding the NAS message.

In the case of the fifth mode, the UE_A 10 and/or the eNB_A 45 and/orthe C-SGN_A 95 may transmit and/or receive the user data by use of thethird transmission and/or reception procedure.

And/or, in the case of the fifth mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt a method for transmitting and/orreceiving the user data by use of the third transmission and/orreception procedure as the initial transmission and/or reception method.

And/or, in the case of the fifth mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may adopt the EPS bearer including the DRB as theDefault Bearer.

The Default Bearer may be the first bearer, or the bearer fortransmitting and/or receiving the user data in the initial transmissionand/or reception method.

The PDN connection having been established when the fifth mode isentered may enter the idle mode of related art depending on a conditionsuch as that no user data is transmitted and/or received.

First identification information in the present embodiment may be aPreferred Network Behavior.

Note that the first identification information may be identificationinformation including meaning of one or more kinds of second to sixthidentification information. In other words, one or more kinds ofidentification information among the second to sixth identificationinformation may be transmitted and/or received with being included inthe first identification information.

The second identification information in the present embodiment may be aUE Control Plane CIoT EPS optimisation Capability. In other words, thesecond identification information may be information indicating that theUE_A 10 has a capability of transmitting and/or receiving the user databy use of the first transmission and/or reception procedure.

The third identification information in the present embodiment may be aUE User Plane CIoT EPS optimisation Capability. In other words, thethird identification information may be information indicating that theUE_A 10 has a capability of transmitting and/or receiving the user databy use of the second transmission and/or reception procedure.

The fourth identification information in the present embodiment may be aUE CIoT EPS optimisation Preference. In other words, the fourthidentification information may be information indicating a user datatransmission and/or reception method which is requested by the UE_A 10.

The fifth identification information in the present embodiment may be aUE S I-u data transfer Capability. In other words, the fifthidentification information may be information indicating that the UE_A10 has a capability of transmitting and/or receiving the user data byuse of the third transmission and/or reception procedure.

The sixth identification information in the present embodiment may beinformation indicating whether to establish the PDN connection.

Seventh identification information in the present embodiment may be aSupported Network Behavior.

Note that the seventh identification information may be identificationinformation including meaning of one or more kinds of eighth tosixteenth identification information. In other words, one or more kindsof identification information among the eighth to sixteenthidentification information may be transmitted and/or received with beingincluded in the seventh identification information.

The eighth identification information in the present embodiment may be aNetwork Control Plane CIoT EPS optimisation Capability. In other words,the eighth identification information may be information indicating thatthe core network_A 90 has a capability of transmitting and/or receivingthe user data by use of the first transmission and/or receptionprocedure.

The ninth identification information in the present embodiment may be aNetwork User Plane CIoT EPS optimisation Capability. In other words, theninth identification information may be information indicating that thecore network_A 90 has a capability of transmitting and/or receiving theuser data by use of the second transmission and/or reception procedure.

The tenth identification information in the present embodiment may be aNetwork Control Plane CIoT EPS optimisation Allowance. In other words,the tenth identification information may be information indicating thatthe core network_A 90 allows transmission and/or reception of the userdata by use of the first transmission and/or reception procedure.

The eleventh identification information in the present embodiment may bea Network User Plane CIoT EPS optimisation Allowance. In other words,the eleventh identification information may be information indicatingthat the core network_A 90 allows transmission and/or reception of theuser data by use of the second transmission and/or reception procedure.

The twelfth identification information in the present embodiment may bea Network CIoT EPS optimisation Preference. In other words, the twelfthidentification information may be information indicating a user datatransmission and/or reception method which is requested by the corenetwork_A 90.

The thirteenth identification information in the present embodiment maybe an Authorized CIoT EPS optimisation Preference. In other words, thethirteenth identification information may be information indicating anauthorized user data transmission and/or reception method.

The fourteenth identification information in the present embodiment maybe a Network S1-u data transfer Capability. In other words, thefourteenth identification information may be information indicating thatthe core network_A 90 has a capability of transmitting and/or receivingthe user data by use of the third transmission and/or receptionprocedure.

The fifteenth identification information in the present embodiment maybe information indicating whether to establish the PDN connection.

The sixteenth identification information in the present embodiment maybe an EPS Bearer ID. The sixteenth identification information may betransmitted and/or received with being included in an Attach Acceptmessage and/or an Activate default EPS bearer context request message.

Seventeenth identification information in the present embodiment may bean EPS Bearer ID. The seventeenth identification information may betransmitted and/or received with being included in a Bearer resourcemodification request message and/or a Modify EPS bearer context requestmessage and/or a Deactivate EPS bearer context request message.

The sixteenth identification information and/or the seventeenthidentification information and/or twenty-sixth identificationinformation may be identification information identifying the SRB and/orthe CRB, or identification information identifying the DRB.

Eighteenth identification information in the present embodiment may beinformation indicating a transmission and/or reception method afterrequested change. The eighteenth identification information may beinformation indicating a method using the first transmission and/orreception procedure, or information indicating a method using the secondtransmission and/or reception procedure.

Nineteenth identification information in the present embodiment may beinformation indicating a type of the RB after requested change. Thenineteenth identification information may be information indicating theSRB, or information indicating the DRB.

Twentieth identification information in the present embodiment may beinformation indicating a mode of the attach complete state afterrequested change. The twentieth identification information may beinformation indicating the first mode, or information indicating thethird mode.

Twenty-first identification information in the present embodiment may beinformation indicating that the transmission and/or reception method isrequested to be changed.

Twenty-second identification information in the present embodiment maybe an Updated UE CIoT EPS optimisation Preference. In other words, thetwenty-second identification information may be information indicatingan updated user data transmission and/or reception method which isrequested by the UE_A 10.

Twenty-third identification information in the present embodiment may bean Updated Network CIoT EPS optimisation Preference. In other words, thetwenty-third identification information may be information indicating anupdated user data transmission and/or reception method which isrequested by the core network_A 90.

Twenty-fourth identification information in the present embodiment maybe information indicating that the PDN connection is requested to bere-established.

Twenty-fifth identification information in the present embodiment may beinformation indicating that the Default Bearer is requested to bere-established.

Twenty-sixth identification information in the present embodiment may bean EPS Bearer ID. The twenty-sixth identification information may betransmitted and/or received with being included in a Modify EPS bearercontext request message and/or a Modify EPS bearer context acceptmessage and/or a Deactivate EPS bearer context accept message.

Twenty-seventh identification information in the present embodiment maybe information indicating a transmission and/or reception method afterauthorized change. The twenty-seventh identification information may beinformation indicating a method using the first transmission and/orreception procedure, or information indicating a method using the secondtransmission and/or reception procedure.

Twenty-eighth identification information in the present embodiment maybe information indicating a type of the RB after authorized change. Thetwenty-eighth identification information may be information indicatingthe SRB, or information indicating the DRB.

Twenty-ninth identification information in the present embodiment may beinformation indicating a mode of the attach complete state afterauthorized change. The twentieth identification information may beinformation indicating the first mode, or information indicating thethird mode.

Thirtieth identification information in the present embodiment may beinformation indicating that the transmission and/or reception method isauthorized to be changed.

Thirty-first identification information in the present embodiment may bean Updated UE CIoT EPS optimisation Preference. In other words, thethirty-first identification information may be information indicating anupdated user data transmission and/or reception method which isrequested by the UE_A 10.

Thirty-second identification information in the present embodiment maybe an Updated Network CIoT EPS optimisation Preference. In other words,the thirty-second identification information may be informationindicating an updated user data transmission and/or reception methodwhich is requested by the core network_A 90.

Thirty-third identification information in the present embodiment may bean Updated Authorized CIoT EPS optimisation Preference. In other words,the thirty-third identification information may be informationindicating an updated authorized user data transmission and/or receptionmethod.

In a case that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95hold the respective pieces of identification information, the UE_A 10and/or the eNB_A 45 and/or the C-SGN_A 95 may have capabilitiesindicated by the respective pieces of identification information.

Additionally, in the present embodiment, in a case that two or morekinds of identification information among the first to thirty-thirdidentification information are transmitted with being included in thesame control message, respective pieces of the identificationinformation may be included and transmitted, or one kind ofidentification information having meanings indicated by respectivepieces of the identification information may be included in the controlmessage.

For example, the first identification information may be identificationinformation having meanings indicated by the second to sixthidentification information.

Note that each piece of identification information may be an informationelement configured as the flag or the parameter.

[1.3.1. Attach Procedure Example]

First, an example of an attach procedure will be described. The attachprocedure is a procedure initiated by the UE_A 10. The attach procedureis a procedure for the UE_A 10 to connect to the network. In otherwords, the attach procedure is a procedure to connect to an accessnetwork including the eNB45, and further, is a procedure to connect to acore network through the access network. The UE_A 10 establishes acommunication path for transmitting and/or receiving the user data toand from the PDN_A 5 by means of the attach procedure.

A trigger for starting the attach procedure by the UE_A 10 may be a timewhen the power is supplied to the terminal, or the like. Additionally,the UE_A 10 may start at an arbitrary timing in a case that the UE_A 10is in a state not connecting to the core network_A 90 regardless of theabove. The UE_A 10 may enter the attach complete state, based onconnection to the core network_A 90 and/or completion of the attachprocedure.

In the following, a description is given of details of an example of theattach procedure.

Hereinafter, an example of the steps of the attach procedure will bedescribed using FIG. 23.

First, the UE_A 10 transmits an Attach Request message to the C-SGN_A 95(S2300). Note that the UE_A 10 may transmit the Attach Request messageto the eNB_A 45, and the transmitted Attach Request message may betransferred to the C-SGN_A 95 via the eNB_A 45.

Additionally, the UE_A 10 may select whether to include a PDNconnectivity request message in the Attach Request message. To be morespecific, the UE_A 10 may select whether to include an ESM messagecontainer containing the PDN connectivity request message in the AttachRequest message.

Furthermore, the UE_A 10 may indicate that establishment of a PDNconnection according to the attach procedure is requested by includingthe PDN connectivity request message and/or the ESM message container inthe Attach Request message.

Conversely, the UE_A 10 may indicate that establishment of a PDNconnection according to the attach procedure is not requested by notincluding the PDN connectivity request message and/or the ESM messagecontainer in the Attach Request message.

In the case that the UE_A 10 includes the PDN connectivity requestmessage in the Attach Request message, in the description of the presentembodiment, the Attach Request message is described as a message inwhich the Attach Request message and the PDN connectivity requestmessage are combined. Furthermore, in the description of the presentembodiment, in a case that an expression “identification information isincluded in the Attach Request message” is used, the expression meansthat the identification information is included in the Attach Requestmessage and/or the PDN connectivity request message.

The UE_A 10 may include at least one or more kinds of identificationinformation among the first to sixth identification information in theAttach Request message. The UE_A 10 may transmit the Attach Requestmessage including one or more kinds of identification information amongthe first to sixth identification information to request a mode of theattach complete state to enter.

Here, one or more kinds of identification information among the first tosixth identification information may not be transmitted to the C-SGN_A95 with being included in the Attach Request message, but may betransmitted with being included in a control message different from theAttach Request message in the attach procedure.

For example, after transmitting the Attach Request message, the UE_A 10may perform a request of EPS Session Management (ESM) information, and atransmission and/or reception procedure of a control message whichresponds based on the request (S2302).

To be more specific, the C-SGN_A 95 transmits an ESM request message tothe UE_A 10. The UE_A 10 receives the ESM request message, and transmitsa response message to the C-SGN_A 95. At this time, the UE_A 10 maytransmit the response message including one or more kinds ofidentification information among the first to sixth identificationinformation.

Here, the UE_A 10 may encrypt and transmit the ESM response message.Furthermore, the UE_A 10 may receive information for encrypting the ESMresponse message from the C-SGN_A 95. The C-SGN_A 95 may transmitinformation for encrypting the NAS message to the UE_A 10 with thereception of the Attach Request message. Note that the NAS message forwhich the information for encrypting the NAS message is transmitted maybe a Security Mode Command message.

The C-SGN_A 95 receives the Attach Request message. Furthermore, theC-SGN_A 95 acquires one or more kinds of identification informationamong the first to sixth identification information based on thereception of the Attach Request message or the reception of the ESMresponse message.

The C-SGN_A 95 may determine to enter the attach complete state for theUE_A 10 and/or determine the attach complete state to enter, based onthe information included in the Attach Request message, subscriberinformation, and the identification information which the C-SGN_A 95has.

For example, the C-SGN_A 95 may select and determine whether the attachcomplete state to enter is the first mode, the second mode, the thirdmode, the fourth mode, or the fifth mode, based on one or more kinds ofidentification information among the first to sixteenth identificationinformation and/or whether or not the ESM message container is includedand/or whether or not the PDN connectivity request message is included.Hereinafter, the selection and determination process described above isreferred to as a first determination and described (S2304).

For example, in a case that the Attach Request message includes thesecond identification information, and/or the fourth identificationinformation indicates the method using the first transmission and/orreception procedure, assume that a first condition is true.

In a case that the C-SGN_A 95 holds the eighth identificationinformation and/or the tenth identification information, and/or thetwelfth identification information and/or the thirteenth identificationinformation indicate the method using the first transmission and/orreception procedure, assume that a second condition is true.

In a case that the Attach Request message includes the thirdidentification information, and/or the fourth identification informationindicates the method using the second transmission and/or receptionprocedure, assume that a third condition is true.

In a case that the C-SGN_A 95 holds the ninth identification informationand/or the eleventh identification information, and/or the twelfthidentification information and/or the thirteenth identificationinformation indicate the method using the second transmission and/orreception procedure, assume that a fourth condition is true.

In a case that the Attach Request message includes the fifthidentification information, assume that a fifth condition is true.

In a case that the C-SGN_A 95 holds the fourteenth identificationinformation, assume that a sixth condition is true.

In a case that the Attach Request message includes the ESM messagecontainer and/or the PDN connectivity request message, and/or the sixthidentification information indicates that the PDN connection isestablished, assume that a seventh condition is true.

In a case that the fifteenth identification information indicates thatthe PDN connection is established, assume that an eighth condition istrue.

In a case that the Attach Request message does not include the ESMmessage container and/or the PDN connectivity request message, and/orthe sixth identification information indicates that the PDN connectionis not established, assume that a ninth condition is true.

In a case that the fifteenth identification information indicates thatthe PDN connection is not established, assume that a tenth condition istrue.

The C-SGN_A 95 may enter the first mode in a case that the firstcondition is true, and/or in a case that the second condition is true,and/or in a case that the seventh condition is true, and/or in a casethat the eighth condition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe first condition is true and the seventh condition is true, and/or ina case that the first condition is true and the eighth condition istrue, and/or in a case that the second condition is true and the seventhcondition is true, and/or in a case that the second condition is trueand the eighth condition is true, and/or in a case that the firstcondition is true and the second condition is true, and/or in a casethat the seventh condition is true and the eighth condition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe first condition is true, the second condition is true, and theseventh condition is true, and/or in a case that the first condition istrue, the second condition is true, and the eighth condition is true,and/or in a case that the first condition is true, the seventh conditionis true, and the eighth condition is true, and/or in a case that thesecond condition is true, the seventh condition is true, and the eighthcondition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe first condition is true, the second condition is true, the seventhcondition is true, and the eighth condition is true.

The C-SGN_A 95 may enter the first mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the second mode in the case that the firstcondition is true, and/or in the case that the second condition is true,and/or in a case that the ninth condition is true, and/or in a case thatthe tenth condition is true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe first condition is true and the ninth condition is true, and/or in acase that the first condition is true and the tenth condition is true,and/or in a case that the second condition is true and the ninthcondition is true, and/or in a case that the second condition is trueand the tenth condition is true, and/or in the case that the firstcondition is true and the second condition is true, and/or in a casethat the ninth condition is true and the tenth condition is true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe first condition is true, the second condition is true, and the ninthcondition is true, and/or in a case that the first condition is true,the second condition is true, and the tenth condition is true, and/or ina case that the first condition is true, the ninth condition is true,and the tenth condition is true, and/or in a case that the secondcondition is true, the ninth condition is true, and the tenth conditionis true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe first condition is true, the second condition is true, the ninthcondition is true, and the tenth condition is true.

The C-SGN_A 95 may enter the second mode in other cases than those ofthe above conditions without limitation.

The C-SGN_A 95 may enter the third mode in a case that the thirdcondition is true, and/or in a case that the fourth condition is true,and/or in the case that the seventh condition is true, and/or in thecase that the eighth condition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe third condition is true and the seventh condition is true, and/or ina case that the third condition is true and the eighth condition istrue, and/or in a case that the fourth condition is true and the seventhcondition is true, and/or in a case that the fourth condition is trueand the eighth condition is true, and/or in a case that the thirdcondition is true and the fourth condition is true, and/or in the casethat the seventh condition is true and the eighth condition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe third condition is true, the fourth condition is true, and theseventh condition is true, and/or in a case that the third condition istrue, the fourth condition is true, and the eighth condition is true,and/or in a case that the third condition is true, the seventh conditionis true, and the eighth condition is true, and/or in a case that thefourth condition is true, the seventh condition is true, and the eighthcondition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe third condition is true, the fourth condition is true, the seventhcondition is true, and the eighth condition is true.

The C-SGN_A 95 may enter the third mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the fourth mode in the case that the thirdcondition is true, and/or in the case that the fourth condition is true,and/or in the case that the ninth condition is true, and/or in the casethat the tenth condition is true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe third condition is true and the ninth condition is true, and/or in acase that the third condition is true and the tenth condition is true,and/or in a case that the fourth condition is true and the ninthcondition is true, and/or in a case that the fourth condition is trueand the tenth condition is true, and/or in the case that the thirdcondition is true and the fourth condition is true, and/or in the casethat the ninth condition is true and the tenth condition is true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe third condition is true, the fourth condition is true, and the ninthcondition is true, and/or in a case that the third condition is true,the fourth condition is true, and the tenth condition is true, and/or ina case that the third condition is true, the ninth condition is true,and the tenth condition is true, and/or in a case that the fourthcondition is true, the ninth condition is true, and the tenth conditionis true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe third condition is true, the fourth condition is true, the ninthcondition is true, and the tenth condition is true.

The C-SGN_A 95 may enter the fourth mode in other cases than those ofthe above conditions without limitation.

The C-SGN_A 95 may enter the fifth mode in a case that the fifthcondition is true, and/or in a case that the sixth condition is true,and/or in the case that the seventh condition is true, and/or in thecase that the eighth condition is true.

Alternatively, the C-SGN_A 95 may enter the fifth mode in a case thatthe fifth condition is true and the seventh condition is true, and/or ina case that the fifth condition is true and the eighth condition istrue, and/or in a case that the sixth condition is true and the seventhcondition is true, and/or in a case that the sixth condition is true andthe eighth condition is true, and/or in a case that the fifth conditionis true and the sixth condition is true, and/or in the case that theseventh condition is true and the eighth condition is true.

Alternatively, C-SGN_A 95 may enter the fifth mode in a case that thefifth condition is true, the sixth condition is true, and the seventhcondition is true, and/or in a case that the fifth condition is true,the sixth condition is true, and the eighth condition is true, and/or ina case that the fifth condition is true, the seventh condition is true,and the eighth condition is true, and/or in a case that the sixthcondition is true, the seventh condition is true, and the eighthcondition is true.

Alternatively, the C-SGN_A 95 may enter the fifth mode in a case thatthe fifth condition is true, the sixth condition is true, the seventhcondition is true, and the eighth condition is true.

The C-SGN_A 95 may enter the fifth mode in other cases than those of theabove conditions without limitation.

The conditions for entering the modes of the attach complete state arenot limited to those described above.

The C-SGN_A 95 may start the procedure for establishing the PDNconnection, based on the reception of the Attach Request message, and/orthe transmission of the Attach Accept message, and/or the firstdetermination.

To be more specific, in the case of entering the first mode and/or thethird mode and/or the fifth mode, based on the first determination, theC-SGN_A 95 may start the procedure for establishing the PDN connection.

In the case of entering the second mode and/or the fourth mode, based onthe first determination, the C-SGN_A 95 may not start and may omit theprocedure for establishing the PDN connection.

The procedure for establishing the PDN connection may be constituted byan IP-CAN session update procedure, and/or transmission and/or receptionof an Activate default EPS bearer context request message, and/ortransmission and/or reception of an Activate default EPS bearer contextaccept message, and/or transmission and/or reception of an RRCconnection reconfiguration request message, and/or transmission and/orreception of an RRC connection reconfiguration complete message, and/ortransmission and/or reception of a bearer configuration message.

The C-SGN_A 95 starts the IP-CAN session update procedure in the case ofentering the first mode and/or the third mode and/or the fifth mode(S2306). The IP-CAN session update procedure may be the same as theknown procedure, and therefore detailed descriptions thereof will beomitted.

The C-SGN_A 95 transmits an Attach Accept message to the eNB_A 45 on thefirst determination and/or on the completion of the IP-CAN sessionupdate procedure (S2308).

Additionally, the C-SGN_A 95 may transmit the Activate default EPSbearer context request message with the Attach Accept message, based onthe first determination.

In a case that the C-SGN_A 95 includes the Activate default EPS bearercontext request message in the Attach Accept message, in the descriptionof the present embodiment, the Attach Accept message is described as amessage in which the Attach Accept message and the Activate default EPSbearer context request message are combined. Furthermore, in thedescription of the present embodiment, in the case that an expression“identification information is included in the Attach Accept message” isused, the expression means that the identification information isincluded in the Attach Accept message and/or the Activate default EPSbearer context request message.

The C-SGN_A 95 may include at least one or more kinds of identificationinformation among the seventh to sixteenth identification information inthe Attach Accept message.

The C-SGN_A 95 may modify and/or newly create one or more kinds ofidentification information among the seventh to sixteenth identificationinformation, based on the first determination, and include the resultingidentification information in the Attach Accept message.

Specifically, the C-SGN_A 95 may include information indicating thedetermined user data transmission and/or reception method in thethirteenth identification information, based on the first determination.

It may be determined, based on the first determination, whether or notthe Activate default EPS bearer context request message is a messagerequesting that the DRB is established.

To be more specific, in the case of entering the first mode. based onthe first determination, the Activate default EPS bearer context requestmessage may be a message not intending to establish the DRB. In thiscase, the Activate default EPS bearer context request message may be aDownlink generic NAS Transport message.

In the case of entering the third mode and/or the fifth mode, based onthe first determination, the Activate default EPS bearer context acceptmessage may be a message intending to establish the DRB.

Note that the C-SGN_A 95 may put a connection state for the UE_A 10 inthe idle mode with the transmission of the Attach Accept message basedon the first determination. In other words, the C-SGN_A 95 may put theconnection state for the UE_A 10 in the idle mode, based on entering theattach complete state. To be more specific, the C-SGN_A 95 may put theconnection state for the UE_A 10 in the idle mode, based on that theattach complete state to enter is the first mode. In other words, in acase that the C-SGN_A 95 transmits the Attach Accept message forentering the attach complete state in the third mode and/or the fifthmode, the C-SGN_A 95 may put the connection state for the UE_A 10 in theactive mode with the transmission of the message.

The eNB_A 45 receives the Attach Accept message, and transmits an RRCmessage including the Attach Accept message to the UE_A 10 (S2310). Notethat the RRC message may be an RRC connection reconfiguration requestmessage. The RRC message may be a Direct Transfer message.

The UE_A 10 receives the RRC message including the Attach Acceptmessage. Furthermore, in a case that one or more kinds of identificationinformation among the seventh to sixteenth identification informationare included in the Attach Accept message, the UE_A 10 acquires eachpiece of identification information.

In order to respond to the received RRC message, the UE_A 10 transmitsan RRC message to the eNB_A 45 (S2314). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives the RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95, based on thereception (S2316).

The UE_A 10 and/or the eNB_A 45 may omit the procedures at S2314 andS2316, based on the first determination.

Additionally, the UE_A 10 transmits an RRC message including an AttachComplete message to the eNB_A 45 based on the reception of the AttachAccept message (S2318).

Additionally, the UE_A 10 may transmit the Activate default EPS bearercontext accept message with the Attach Complete message, based on thefirst determination. Here, the Activate default EPS bearer contextaccept message may be a response message to the Activate default EPSbearer context request message.

In the case that the UE_A 10 includes the Activate default EPS bearercontext accept message in the Attach Complete message, in thedescription of the present embodiment, the Attach Complete message isdescribed as a message in which the Attach Complete message and theActivate default EPS bearer context accept message are combined.Furthermore, in the description of the present embodiment, in the casethat an expression “identification information is included in the AttachComplete message” is used, the expression means that the identificationinformation is included in the Attach Complete message and/or theActivate default EPS bearer context accept message.

Note that the RRC message to be transmitted with including the AttachComplete message may be a Direct Transfer message.

The UE_A 10 enters the attach complete state, based on the reception ofthe Attach Accept message and/or the transmission of the Attach Completemessage.

The UE_A 10 may recognize and determine the attach complete state toenter, based the information included in the Attach Accept message andthe identification information which the UE_A 10 has.

For example, the UE_A 10 may authorize and determine whether the attachcomplete state to enter is the first mode, the second mode, the thirdmode, the fourth mode, or the fifth mode, based on one or more kinds ofidentification information among the first to sixteenth identificationinformation, and/or whether or not the ESM message container isincluded, and/or whether or not the Activate default EPS bearer contextaccept message is included. Hereinafter, the authorization anddetermination process described above is referred to as a seconddetermination and described (S2312).

For example, in a case that the UE_A 10 holds the second identificationinformation, and/or the fourth identification information indicates themethod using the first transmission and/or reception procedure, assumethat an eleventh condition is true.

Furthermore, in a case that the Attach Accept message includes theeighth identification information and/or the tenth identificationinformation, and/or the twelfth identification information and/or thethirteenth identification information indicate the method using thefirst transmission and/or reception procedure, and/or the sixteenthidentification information is identification information identifying theSRB and/or the CRB, assume that a twelfth condition is true.

Furthermore, in a case that the UE_A 10 holds the third identificationinformation, and/or the fourth identification information indicates themethod using the second transmission and/or reception procedure, assumethat a thirteenth condition is true.

Furthermore, in a case that the Attach Accept message includes the ninthidentification information and/or the eleventh identificationinformation, and/or the twelfth identification information and/or thethirteenth identification information indicate the method using thesecond transmission and/or reception procedure, and/or the sixteenthidentification information is identification information identifying theDRB, assume that a fourteenth condition is true.

Furthermore, in a case that the UE_A 10 holds the fifth identificationinformation, assume that a fifteenth condition is true.

Furthermore, in a case that the Attach Accept message includes thefourteenth identification information, and/or the sixteenthidentification information is identification information identifying theDRB, assume that a sixteenth condition is true.

Furthermore, in a case that the Attach Accept message includes the ESMmessage container and/or the Activate default EPS bearer context requestmessage, and/or the sixth identification information indicates that thePDN connection is established, assume that a seventeenth condition istrue.

Furthermore, in a case that the fifteenth identification informationindicates that the PDN connection is established, assume that aneighteenth condition is true.

Furthermore, in a case that the Attach Accept message does not includethe ESM message container and/or the Activate default EPS bearer contextrequest message, and/or the sixth identification information indicatesthat the PDN connection is not established, assume that a nineteenthcondition is true.

Furthermore, in a case that the fifteenth identification informationindicates that the PDN connection is not established, assume that atwentieth condition is true.

The C-SGN_A 95 may enter the first mode in a case that the eleventhcondition is true, and/or in a case that the twelfth condition is true,and/or in a case that the seventeenth condition is true, and/or in acase that the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe eleventh condition is true and the seventeenth condition is true,and/or in a case that the eleventh condition is true and the eighteenthcondition is true, and/or in a case that the twelfth condition is trueand the seventeenth condition is true, and/or in a case that the twelfthcondition is true and the eighteenth condition is true, and/or in a casethat the eleventh condition is true and the twelfth condition is true,and/or in a case that the seventeenth condition is true and theeighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe eleventh condition is true, the twelfth condition is true, and theseventeenth condition is true, and/or in a case that the eleventhcondition is true, the twelfth condition is true, and the eighteenthcondition is true, and/or in a case that the eleventh condition is true,the seventeenth condition is true, and the eighteenth condition is true,and/or in a case that the twelfth condition is true, the seventeenthcondition is true, and the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the first mode in a case thatthe eleventh condition is true, the twelfth condition is true, theseventeenth condition is true, and the eighteenth condition is true.

The C-SGN_A 95 may enter the first mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the second mode in the case that the eleventhcondition is true, and/or in the case that the twelfth condition istrue, and/or in a case that the nineteenth condition is true, and/or ina case that the twentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe eleventh condition is true and the nineteenth condition is true,and/or in a case that the eleventh condition is true and the twentiethcondition is true, and/or in a case that the twelfth condition is trueand the nineteenth condition is true, and/or in a case that the twelfthcondition is true and the twentieth condition is true, and/or in thecase that the eleventh condition is true and the twelfth condition istrue, and/or in a case that the nineteenth condition is true and thetwentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe eleventh condition is true, the twelfth condition is true, and thenineteenth condition is true, and/or in a case that the eleventhcondition is true, the twelfth condition is true, and the twentiethcondition is true, and/or in a case that the eleventh condition is true,the nineteenth condition is true, and the twentieth condition is true,and/or in a case that the twelfth condition is true, the nineteenthcondition is true, and the twentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the second mode in a case thatthe eleventh condition is true, the twelfth condition is true, thenineteenth condition is true, and the twentieth condition is true.

The C-SGN_A 95 may enter the second mode in other cases than those ofthe above conditions without limitation.

The C-SGN_A 95 may enter the third mode in a case that the thirteenthcondition is true, and/or in a case that the fourteenth condition istrue, and/or in a case that the seventeenth condition is true, and/or ina case that the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe thirteenth condition is true and the seventeenth condition is true,and/or in a case that the thirteenth condition is true and theeighteenth condition is true, and/or in a case that the fourteenthcondition is true and the seventeenth condition is true, and/or, in acase that the fourteenth condition is true and the eighteenth conditionis true, and/or in a case that the thirteenth condition is true and thefourteenth condition is true, and/or in a case that the seventeenthcondition is true and the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe thirteenth condition is true, the fourteenth condition is true, andthe seventeenth condition is true, and/or in a case that the thirteenthcondition is true, the fourteenth condition is true, and the eighteenthcondition is true, and/or in a case that the thirteenth condition istrue, the seventeenth condition is true, and the eighteenth condition istrue, and/or in a case that the fourteenth condition is true, theseventeenth condition is true, and the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the third mode in a case thatthe thirteenth condition is true, the fourteenth condition is true, theseventeenth condition is true, and the eighteenth condition is true.

The C-SGN_A 95 may enter the third mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the fourth mode in the case that the thirteenthcondition is true, and/or in the case that the fourteenth condition istrue, and/or in the case that the nineteenth condition is true, and/orin the case that the twentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe thirteenth condition is true and the nineteenth condition is true,and/or in a case that the thirteenth condition is true and the twentiethcondition is true, and/or in a case that the fourteenth condition istrue and the nineteenth condition is true, and/or in a case that thefourteenth condition is true and the twentieth condition is true, and/orin the case that the thirteenth condition is true and the fourteenthcondition is true, and/or in the case that the nineteenth condition istrue and the twentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe thirteenth condition is true, the fourteenth condition is true, andthe nineteenth condition is true, and/or in a case that the thirteenthcondition is true, the fourteenth condition is true, and the twentiethcondition is true, and/or in a case that the thirteenth condition istrue, the nineteenth condition is true, and the twentieth condition istrue, and/or in a case that the fourteenth condition is true, thenineteenth condition is true, and the twentieth condition is true.

Alternatively, the C-SGN_A 95 may enter the fourth mode in a case thatthe thirteenth condition is true, the fourteenth condition is true, thenineteenth condition is true, and the twentieth condition is true.

The C-SGN_A 95 may enter the fourth mode in other cases than those ofthe above conditions without limitation.

The C-SGN_A 95 may enter the fifth mode in a case that the fifteenthcondition is true, and/or in case that the sixteenth condition is true,and/or in the case that the seventeenth condition is true, and/or in thecase that the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the fifth mode in a case thatthe fifteenth condition is true and the seventeenth condition is true,and/or in a case that the fifteenth condition is true and the eighteenthcondition is true, and/or in a case that the sixteenth condition is trueand the seventeenth condition is true, and/or in a case that thesixteenth condition is true and the eighteenth condition is true, and/orin a case that the fifteenth condition is true and the sixteenthcondition is true, and/or in the case that the seventeenth condition istrue and the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the fifth mode in a case thatthe fifteenth condition is true, the sixteenth condition is true, andthe seventeenth condition is true, and/or in a case that the fifteenthcondition is true, the sixteenth condition is true, and the eighteenthcondition is true, and/or in a case that the fifteenth condition istrue, the seventeenth condition is true, and the eighteenth condition istrue, and/or in a case that the sixteenth condition is true, theseventeenth condition is true, and the eighteenth condition is true.

Alternatively, the C-SGN_A 95 may enter the fifth mode in a case thatthe fifteenth condition is true, the sixteenth condition is true, theseventeenth condition is true, and the eighteenth condition is true.

The C-SGN_A 95 may enter the fifth mode in other cases than those of theabove conditions without limitation.

The conditions for entering the modes of the attach complete state arenot limited to those described above.

The UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may establish thePDN connection, based on the transmission and/or reception of the AttachAccept message, and/or the transmission and/or reception of the AttachComplete message, and/or a fourth determination. On establishing the PDNconnection, the Default Bearer may be established. The RB constitutingthe Default Bearer may be a DRB. Alternatively, the RB constituting theDefault Bearer may be an SRB.

To be more specific, in a case that the attach complete state is in thefirst mode and/or the third mode and/or the fifth mode, the UE_A 10and/or the eNB_A 45 and/or the C-SGN_A 95 may establish the PDNconnection and/or the Default Bearer and/or and the SRB.

In a case that the attach complete state is in the second mode and/orthe fourth mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95may not establish the PDN connection and/or the Default Bearer.

In a case the attach complete state is in the third mode and/or thefifth mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 mayestablish the DRB.

In the case that the attach complete state is in the first mode, theUE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may not establish theDRB. In other words, in the case that the attach complete state is inthe first mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95may establish the SRB without establishing the DRB.

The eNB_45 receives the RRC message including the Attach Completemessage, and transmits the Attach Complete message to the C-SGN_A 95(S2320).

Additionally, the UE_A 10 may enter the idle mode with the transmissionof the Attach Complete message, based on the second determination. To bemore specific, the UE_A 10 may enter the idle mode with the transmissionof the Attach Complete message in the case that the attach completestate to enter is the third mode and/or the fifth mode.

Alternatively, the UE_A 10 may receive the RRC message from the eNB_A 45as the response to the Direct Transfer message including the AttachComplete message, and may enter the idle mode with the reception of theresponse message, based on the second determination.

As a more detailed example, the UE_A 10 may transmit the Attach Completemessage and/or Direct Transfer message including identificationinformation indicating that the UE_A 10 enters the idle mode.

Furthermore, the eNB_A 45 which receives the Direct Transfer message maytransmit an RRC message to be a response to the UE_A 10, based on thereceived identification information. As described above, the RRC messageto be the response may be a message for allowing the entering the idlemode.

In other words, the UE_A 10 can select whether to enter the idle mode orto maintain the active mode, based on the second determination.

The C-SGN_A 95 receives the Attach Complete message.

The C-SGN_A 95 may make the connection state for the UE_A 10 enter theidle mode, based on the reception of the Attach Complete message.

In other words, the C-SGN_A 95 may manage the state of the UE_A 10 asthe idle mode, based on the transmission of the Attach Accept message orthe reception of the Attach Complete message.

To be more specific, the C-SGN_A 95 may manage the state of the UE_A 10as the idle mode, based on the transmission of the Attach Accept messageor the reception of the Attach Complete message in a case that theentered attach complete state is in the third mode and/or the fifthmode.

The UE_A 10 and/or the eNB_A 45 may identify the type of the RBestablished as the Default Bearer, based on the sixteenth identificationinformation.

For example, the UE_A 10 and/or the eNB_A 45 may recognize that the SRBand/or the CRB are established as the Default Bearer in the case thatthe sixteenth identification information is the identificationinformation identifying the SRB and/or the CRB.

The UE_A 10 and/or the eNB_A 45 may recognize that the DRB isestablished as the Default Bearer in the case that the sixteenthidentification information is the identification information identifyingthe DRB.

By the above-described steps, the UE_A 10 connects to the network, andcompletes the attach procedure. On the completion of the attachprocedure, the UE_A 10 and/or the C-SGN_A 95 enter the attach completestate.

Note that the UE_A 10 can acquire the UE contexts illustrated in FIG. 21from the core network_A 90 by the attach procedure and store thecontexts.

To be more specific, in the case that the entered attach complete stateis in the first mode and/or the third mode and/or the fifth mode, theUE_A 10 can acquire the UE contexts illustrated in FIG. 21 from the corenetwork_A 90 by the attach procedure and store the contexts.

Moreover, in a case that the entered attach complete state is in thesecond mode and/or the fourth mode, the UE_A 10 can acquire other UEcontexts than the UE context for each PDN connection and/or UE contextfor each bearer among the UE context illustrated in FIG. 21 from thecore network_A 90 by the attach procedure and store the contexts.

Furthermore, the C-SGN_A 95 can acquire each of the contexts A to Eillustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the attach procedure and store the context.

To be more specific, in the case that the entered attach complete stateis in the first mode and/or the third mode and/or the fifth mode, theC-SGN_A 95 can acquire each of the contexts A to E illustrated in FIG.19 from the UE_A 10, the eNB_A 45, or the HSS_A 50 by the attachprocedure and store the context.

Moreover, in the case that the entered attach complete state is in thesecond mode and/or the fourth mode, the C-SGN_A 95 can acquire othercontexts than the EPS bearer context for each PDN connection and/or EPSbearer context for each bearer among the respective contexts A to Eillustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the attach procedure and store the contexts.

[1.3.1.1. Attach Procedure Modification Example]

Although the attach procedure is described in a case that the corenetwork_A 90 in the attach procedure example described above is a corenetwork configured by including the C-SGN_A 95 described using FIGS. 3Aand 3B, the core network_A 90 may be a core network configured byincluding the PGW_A 30, the SGW_A 35, the MME_A 40, or the like asdescribed using FIGS. 2A and 2B.

In this case, the NAS message such as the Attach Request message, theAttach Complete message transmitted by the UE_A 10 described in thisprocedure is received by the MME 45, not by the C-SGN_A 95.

Accordingly, the reception and processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and processes of the NAS message such asthe Attach Accept message by the C-SGN_A 95 in the above description canbe replaced with those performed by the MME_A 40.

[1.3.2. Example of PDN Connectivity Procedure]

Next, an example of the PDN connectivity procedure will be described.The PDN connectivity procedure is a procedure initiated by the UE_A 10.The PDN connectivity procedure is a procedure for establishing acommunication path for the UE_A 10 to transmit and/or receive the userdata to and from the PDN_A 5. In other words, the PDN connectivityprocedure is a procedure for establishing the PDN connection used totransmit and/or receive the user data.

A trigger for starting the PDN connectivity procedure by the UE_A 10 maybe a time when the power is supplied to the terminal, or a time when theattach procedure is completed. The UE_A 10 may start the PDNconnectivity procedure, based on entering the attach complete state inthe second mode and/or the fourth mode on the completion of the attachprocedure. Moreover, regardless of the above, the UE_A 10 may start PDNconnectivity procedure at any timing.

After the completion of the PDN connectivity procedure, the UE 10establishes the PDN connection with the PDN_A 5. Accordingly, the UE_A10 may change the mode of the attach complete state, based on thecompletion of the PDN connectivity procedure.

A description is given below of details of the example of the PDNconnectivity procedure.

The example of the steps of the PDN connectivity procedure will bedescribed below using FIG. 24.

First, the UE_A 10 transmits a PDN connectivity request message to theC-SGN_A 95 (S2400). Note that the UE_A 10 may transmit the PDNconnectivity request message to the eNB_A 45, and the transmitted PDNconnectivity request message may be transferred to the C-SGN_A 95 viathe eNB 45.

The UE_A 10 may include at least one or more kinds of identificationinformation among the first to fifth identification information in thePDN connectivity request message. The UE_A 10 may transmit the PDNconnectivity request message including one or more kinds ofidentification information among the first to fifth identificationinformation to request a type of the PDN connection to establish and/ora mode of the attach complete state to enter.

The C-SGN_A 95 receives the PDN connectivity request message.Furthermore, the C-SGN_A 95 acquires one or more kinds of identificationinformation among the first to fifth identification information, basedon the reception of the PDN connectivity request message.

The C-SGN_A 95 may establish the PDN connection for the UE_A 10 and/ordetermine the attach complete state to enter, based on the informationincluded in the PDN connectivity request message, subscriberinformation, and the identification information which the C-SGN_A 95has.

For example, the C-SGN_A 95 may select and determine whether the attachcomplete state to enter is the first mode, the third mode, or the fifthmode, based on one or more kinds of identification information among thefirst to sixteenth identification information. Hereinafter, theselection and determination process described above is referred to as athird determination and described (S2402).

For example, in a case that the PDN connectivity request messageincludes the second identification information, and/or the fourthidentification information indicates the method using the firsttransmission and/or reception procedure, assume that a first conditionis true.

In a case that the C-SGN_A 95 holds the eighth identificationinformation and/or the tenth identification information, and/or thetwelfth identification information and/or the thirteenth identificationinformation indicate the method using the first transmission and/orreception procedure, assume that a second condition is true.

In a case that the PDN connectivity request message includes the thirdidentification information, and/or the fourth identification informationindicates the method using the second transmission and/or receptionprocedure, assume that a third condition is true.

In a case that the C-SGN_A 95 holds the ninth identification informationand/or the eleventh identification information, and/or the twelfthidentification information and/or the thirteenth identificationinformation indicate the method using the second transmission and/orreception procedure, assume that a fourth condition is true.

In a case that the PDN connectivity request message includes the fifthidentification information, assume that a fifth condition is true.

In a case that the C-SGN_A 95 holds the fourteenth identificationinformation, assume that a sixth condition is true.

The C-SGN_A 95 may enter the first mode in a case that the firstcondition is true, and/or in a case that the second condition is true,and/or in a case that the first condition is true and the secondcondition is true.

The C-SGN_A 95 may enter the first mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the third mode in a case that the thirdcondition is true, and/or in a case that the fourth condition is true,and/or in a case that the third condition is true and the fourthcondition is true.

The C-SGN_A 95 may enter the third mode in other cases than those of theabove conditions without limitation.

The C-SGN_A 95 may enter the fifth mode in a case that the fifthcondition is true, and/or in a case that the sixth condition is true,and/or in a case that the fifth condition is true and the sixthcondition is true.

The C-SGN_A 95 may enter the fifth mode in other cases than those of theabove conditions without limitation.

The conditions for entering the modes of the attach complete state arenot limited to those described above.

The C-SGN_A 95 may start the procedure for establishing the PDNconnection based on the reception of the PDN connectivity requestmessage, and/or transmission of the Activate default EPS bearer contextrequest message, and/or the third determination.

The procedure for establishing the PDN connection may be constituted byan IP-CAN session update procedure, and/or transmission and/or receptionof an Activate default EPS bearer context request message, and/ortransmission and/or reception of an Activate default EPS bearer contextaccept message, and/or transmission and/or reception of an RRCconnection reconfiguration request message, and/or transmission and/orreception of an RRC connection reconfiguration complete message, and/ortransmission and/or reception of a bearer configuration message.

The C-SGN_A 95 starts the IP-CAN session update procedure (S2404). TheIP-CAN session update procedure may be the same as the known procedure,and therefore detailed descriptions thereof will be omitted.

The C-SGN_A 95 transmits the Activate default EPS bearer context requestmessage to the eNB_A 45 on the third determination and/or on thecompletion of the IP-CAN session update procedure (S2406). The Activatedefault EPS bearer context request message may be a response message tothe PDN connectivity request message.

The C-SGN_A 95 may include at least one or more kinds of identificationinformation among the seventh to sixteenth identification information inthe Activate default EPS bearer context request message.

The C-SGN_A 95 may modify and/or newly create one or more kinds ofidentification information among the seventh to sixteenth identificationinformation, based on the third determination, and include the resultingidentification information in the Activate default EPS bearer contextrequest message.

Specifically, the C-SGN_A 95 may include information indicating thedetermined user data transmission and/or reception method in thethirteenth identification information, based on the third determination.

It may be determined, based on the third determination, whether or notthe Activate default EPS bearer context request message is a messagerequesting that the DRB is established.

To be more specific, in the case of entering the first mode. based onthe third determination, the Activate default EPS bearer context requestmessage may be a message not intending to establish the DRB. In thiscase, the Activate default EPS bearer context request message may be aDownlink generic NAS Transport message.

In the case of entering the third mode and/or the fifth mode, based onthe third determination, the Activate default EPS bearer context acceptmessage may be a message intending to establish the DRB.

Note that the C-SGN_A 95 may put the connection state for the UE_A 10 inthe idle mode with the transmission of the Activate default EPS bearercontext request message based on the third determination. In otherwords, the C-SGN_A 95 may put the connection state for the UE_A 10 inthe idle mode, based on entering the attach complete state. To be morespecific, the C-SGN_A 95 may put the connection state for the UE_A 10 inthe idle mode, based on that the attach complete state to enter is thefirst mode. In other words, in a case that the C-SGN_A 95 transmits theActivate default EPS bearer context request message for entering theattach complete state in the third mode and/or the fifth mode, theC-SGN_A 95 may put the connection state for the UE_A 10 in the activemode with the transmission of the message.

The eNB_A 45 receives the Activate default EPS bearer context requestmessage, and transmits an RRC message including the Activate default EPSbearer context request message to the UE_A 10 (S2408). Note that the RRCmessage may be an RRC connection reconfiguration request message. TheRRC message may be a Direct Transfer message.

The UE_A 10 receives the RRC message including the Activate default EPSbearer context request message. Furthermore, in a case that one or morekinds of identification information among the seventh to sixteenthidentification information are included in the Activate default EPSbearer context request message, the UE_A 10 acquires each piece ofidentification information.

In order to respond to the received RRC message, the UE_A 10 transmitsan RRC message to the eNB_A 45 (S2412). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives the RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95, based on thereception (S2414).

The UE_A 10 and/or the eNB_A 45 may omit the procedures at S2412 andS2414, based on the third determination.

The UE_A 10 transmits an RRC message including the Activate default EPSbearer context accept message to the eNB_A 45, based on the reception ofthe Activate default EPS bearer context request message (S2416). Here,the Activate default EPS bearer context accept message may be a responsemessage to the Activate default EPS bearer context request message.

Note that the RRC message to be transmitted with including the Activatedefault EPS bearer context accept message may be a Direct Transfermessage.

The UE_A 10 enters the attach complete state, based on the reception ofthe Activate default EPS bearer context request message and/or thetransmission of the Activate default EPS bearer context accept message.

The UE_A 10 may recognize and determine the attach complete state toenter, based on the information included in the Activate default EPSbearer context request message and the identification information whichthe UE_A 10 has.

For example, the UE_A 10 may authorize and determine whether the attachcomplete state to enter is the first mode, the third mode, or the fifthmode, based on one or more kinds of identification information among thefirst to sixteenth identification information. Hereinafter, theauthorization and determination process described above is referred toas a fourth determination and described (S2410).

For example, in a case that the UE_A 10 holds the second identificationinformation, and/or the fourth identification information indicates themethod using the first transmission/reception procedure, assume that theeleventh condition is true.

Furthermore, in a case that the Activate default EPS bearer contextrequest message includes the eighth identification information and/orthe tenth identification information, and/or, the twelfth identificationinformation and/or the thirteenth identification information indicatethe method using the first transmission and/or reception procedure,and/or the sixteenth identification information is identificationinformation identifying the SRB and/or the CRB, assume that the twelfthcondition is true.

Furthermore, in a case that the UE_A 10 holds the third identificationinformation, and/or the fourth identification information indicates themethod using the second transmission and/or reception procedure, assumethat the thirteenth condition is true.

Furthermore, in a case that the Activate default EPS bearer contextrequest message includes the ninth identification information and/or theeleventh identification information, and/or the twelfth identificationinformation and/or the thirteenth identification information indicatethe method using the second transmission and/or reception procedure,and/or the sixteenth identification information is identificationinformation identifying the DRB, assume that the fourteenth condition istrue.

Furthermore, in a case that the UE_A 10 holds the fifth identificationinformation, assume that the fifteenth condition is true.

Furthermore, in a case that the Activate default EPS bearer contextrequest message includes the fourteenth identification information,and/or the sixteenth identification information is identificationinformation identifying the DRB, assume that the sixteenth condition istrue.

The UE_A 10 may enter the first mode in a case that the eleventhcondition is true, and/or in a case that the twelfth condition is true,and/or in a case that the eleventh condition is true and the twelfthcondition is true.

The UE_A 10 may enter the first mode in other cases than those of theabove conditions without limitation.

The UE_A 10 may enter the third mode in a case that the thirteenthcondition is true, and/or in a case that the fourteenth condition istrue, and/or in a case that the thirteenth condition is true and thefourteenth condition is true.

The UE_A 10 may enter the third mode in other cases than those of theabove conditions without limitation.

The UE_A 10 may enter the fifth mode in a case that the fifteenthcondition is true, and/or in a case that the sixteenth condition istrue, and/or in a case that the fifteenth condition is true and thesixteenth condition is true.

The UE_A 10 may enter the fifth mode in other cases than those of theabove conditions without limitation.

The conditions for entering the modes of the attach complete state arenot limited to those described above.

The UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may establish thePDN connection, based on the transmission and/or reception of theActivate default EPS bearer context request message, and/or thetransmission and/or reception of the Activate default EPS bearer contextaccept message, and/or the fourth determination. On establishing the PDNconnection, the Default Bearer may be established. The RB constitutingthe Default Bearer may be a DRB. Alternatively, the RB constituting theDefault Bearer may be an SRB.

To be more specific, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 may establish the PDN connection and/or the Default Bearer and/or theSRB.

In the case the attach complete state is in the third mode and/or thefifth mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 mayestablish the DRB.

In the case that the attach complete state is in the first mode, theUE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may not establish theDRB. In other words, in the case that the attach complete state is inthe first mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95may establish the SRB without establishing the DRB.

The eNB_45 receives the RRC message including the Activate default EPSbearer context accept message, and transmits the Activate default EPSbearer context accept message to the C-SGN_A 95 (S2418).

Additionally, the UE_A 10 may enter the idle mode with the transmissionof the Activate default EPS bearer context accept message, based on thefourth determination. To be more specific, the UE_A 10 may enter theidle mode with the transmission of the Activate default EPS bearercontext accept message in the case that the attach complete state toenter is the third mode and/or the fifth mode.

Alternatively, the UE_A 10 may receive the RRC message from the eNB_A 45as the response to the Direct Transfer message including the Activatedefault EPS bearer context accept message, and may enter the idle modewith the reception of the response message, based on the fourthdetermination.

As a more detailed example, the UE_A 10 may transmit the Activatedefault EPS bearer context accept message and/or Direct Transfer messageincluding identification information indicating that the UE_A 10 entersthe idle mode.

Furthermore, the eNB_A 45 which receives the Direct Transfer message maytransmit an RRC message to be a response to the UE_A 10, based on thereceived identification information. As described above, the RRC messageto be the response may be a message for allowing the entering the idlemode.

In other words, the UE_A 10 can select whether to enter the idle mode orto maintain the active mode, based on the fourth determination.

The C-SGN_A 95 receives the Activate default EPS bearer context acceptmessage.

The C-SGN_A 95 may make the connection state for the UE_A 10 enter theidle mode, based on the reception of the Activate default EPS bearercontext accept message.

In other words, the C-SGN_A 95 may manage the state of the UE_A 10 asthe idle mode, based on the transmission of the Activate default EPSbearer context request message or the reception of the Activate defaultEPS bearer context accept message.

To be more specific, the C-SGN_A 95 may manage the state of the UE_A 10as the idle mode, based on the transmission of the Activate default EPSbearer context request message or the reception of the Activate defaultEPS bearer context accept message in a case that the entered attachcomplete state is in the third mode and/or the fifth mode.

The UE_A 10 and/or the eNB_A 45 may identify the type of the RBestablished as the Default Bearer, based on the sixteenth identificationinformation.

For example, the UE_A 10 and/or the eNB_A 45 may recognize that the SRBand/or the CRB are established as the Default Bearer in the case thatthe sixteenth identification information is the identificationinformation identifying the SRB and/or the CRB.

The UE_A 10 and/or the eNB_A 45 may recognize that the DRB isestablished as the Default Bearer in the case that the sixteenthidentification information is the identification information identifyingthe DRB.

By the above-described steps, the UE_A 10 connects to the network, andcompletes the first PDN connectivity procedure. On the completion of thefirst PDN connectivity procedure, the UE_A 10 and/or the C-SGN_A 95 maychange the mode of the attach complete state.

Note that the UE_A 10 can acquire the UE contexts illustrated in FIG. 21from the core network_A 90 by the PDN connectivity procedure and storethe contexts.

To be more specific, the UE_A 10 can acquire the UE context for each PDNconnection and/or UE context for each bearer among the UE contextsillustrated in FIG. 21 from the core network_A 90 by the PDNconnectivity procedure and store the contexts.

Furthermore, the C-SGN_A 95 can acquire each of the contexts A to Eillustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the PDN connectivity procedure and store the context.

To be more specific, the C-SGN_A 95 can acquire the EPS bearer contextfor each PDN connection and/or EPS bearer context for each bearer amongthe contexts A to E illustrated in FIG. 19 from the UE_A 10, the eNB_A45, or the HSS_A 50 by the PDN connectivity procedure and store thecontexts.

[1.3.2.1. Modification Example of PDN Connectivity Procedure]

Although the PDN connectivity procedure is described in a case that thecore network_A 90 in the PDN connectivity procedure example describedabove is a core network configured by including the C-SGN_A 95 describedusing FIGS. 3A and 3B, the core network_A 90 may be a core networkconfigured by including the PGW_A 30, the SGW_A 35, the MME_A 40, or thelike as described using FIGS. 2A and 2B.

In this case, the NAS message such as the PDN connectivity requestmessage, the Activate default EPS bearer context accept messagetransmitted by the UE_A 10 described in this procedure is received bythe MME 45, not by the C-SGN_A 95.

Accordingly, the reception and processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and processes of the NAS message such asthe Activate default EPS bearer context request message by the C-SGN_A95 in the above description can be replaced with those performed by theMME_A 40.

[1.3.3. Example of Transmission and/or Reception Method ChangeProcedure]

First, an example of the transmission and/or reception method changeprocedure will be described. The transmission and/or reception methodchange procedure is a procedure initiated by the UE_A 10 and/or the corenetwork_A 90. In other words, the transmission and/or reception methodchange procedure includes a procedure initiated by the UE_A 10 and aprocedure initiated by the C-SGN_A 95.

The transmission and/or reception method change procedure is a procedurefor the UE_A 10 and/or the C-SGN_A 95 to change the transmission and/orreception method used for the transmission and/or reception of the userdata. In other words, the transmission and/or reception method changeprocedure is a procedure for changing the attach complete state of theUE_A 10 and/or the C-SGN_A 95.

The UE_A 10 and/or the C-SGN_A 95 may start the transmission and/orreception method change procedure at a time when the attach procedureand/or the PDN connectivity procedure are completed. Additionally, theUE_A 10 and/or the C-SGN_A 95 may start the transmission and/orreception method change procedure at an arbitrary timing in a case thatthe UE_A 10 is in a state connecting to the core network_A 90 regardlessof the above.

A trigger for starting the transmission and/or reception method changeprocedure may be an operation on the UE, or an operator policy.

To be more specific, a trigger for starting the transmission and/orreception method change procedure to be initiated by the UE_A 10 may bebased on the operation on the UE.

A trigger for starting the transmission and/or reception method changeprocedure initiated by the core network_A 90 may be not based on thereception of the Bearer resource modification request messagetransmitted by the UE_A 10, but based on the network policy of theoperator.

The UE_A 10 and/or the C-SGN_A 95 are allowed to perform thetransmission and/or reception of the user data by use of a newtransmission and/or reception method after the completion of thetransmission and/or reception method change procedure. Accordingly, theUE_A 10 and/or the C-SGN_A 95 may change the mode of the attach completestate, based on the completion of the transmission and/or receptionmethod change procedure.

Hereinafter, a description is give of details of the transmission and/orreception method change procedure initiated by the UE_A 10 as a firsttransmission and/or reception method change procedure. Furthermore, adescription is given of details of the transmission and/or receptionmethod change procedure initiated by the C-SGN_A 95 as a secondtransmission and/or reception method change procedure and a thirdtransmission and/or reception method change procedure.

[1.3.3.1. Example of First Transmission and/or Reception Method ChangeProcedure]

The example of the steps of the first transmission and/or receptionmethod change procedure will be described below using FIG. 25.

First, the UE_A 10 transmits a Bearer resource modification requestmessage to the C-SGN_A 95 (S2500). Note that the UE_A 10 may transmitthe Bearer resource modification request message to the eNB_A 45, andthe transmitted Bearer resource modification request message may betransferred to the C-SGN_A 95 via the eNB 45.

The UE_A 10 may include at least one or more kinds of identificationinformation among the seventeenth to twenty-second identificationinformation in the Bearer resource modification request message. TheUE_A 10 may transmit the Bearer resource modification request messageincluding one or more kinds of identification information among theseventeenth to twenty-second identification information to requestchange of the user data transmission and/or reception method and/or atype of the user data transmission and/or reception method after thechange.

The C-SGN_A 95 receives the Bearer resource modification requestmessage. Furthermore, the C-SGN_A 95 acquires one or more kinds ofidentification information among the seventeenth to twenty-secondidentification information, based on the reception of the Bearerresource modification request message.

The C-SGN_A 95 may determine the user data transmission and/or receptionmethod after the change for the UE_A 10 and/or the attach complete stateto enter, based on the information included in the Bearer resourcemodification request message, subscriber information, and theidentification information which the C-SGN_A 95 has.

For example, the C-SGN_A 95 may select and determine whether the userdata transmission and/or reception method after the change is the methodusing the first transmission and/or reception procedure, or the methodusing the second transmission and/or reception procedure, based on oneor more kinds of identification information among the first totwenty-second identification information. In other words, the C-SGN_A 95may select and determine whether the attach complete state to enter isthe first mode, or the third mode, based on one or more kinds ofidentification information among the first to twenty-secondidentification information. Hereinafter, the selection and determinationprocess described above is referred to as a fifth determination anddescribed (S2502).

For example, the C-SGN_A 95 may change the user data transmission and/orreception method into the method using the first transmission and/orreception procedure, or may enter the first mode, in a case that theC-SGN_A 95 holds the second identification information and/or the eighthidentification information and/or the tenth identification information,and/or the Bearer resource modification request message includes thetwenty-first identification information, and/or the eighteenthidentification information and/or the twenty-second identificationinformation indicate the method using the first transmission and/orreception procedure, and/or the nineteenth identification informationindicates the SRB, and/or the twentieth identification informationindicates the first mode.

Furthermore, the C-SGN_A 95 may change the user data transmission and/orreception method into the method using the second transmission and/orreception procedure, or may enter the third mode, in a case that theC-SGN_A 95 holds the third identification information and/or the ninthidentification information and/or the eleventh identificationinformation, and/or the Bearer resource modification request messageincludes the twenty-first identification information, and/or theeighteenth identification information and/or the twenty-secondidentification information indicate the method using the secondtransmission and/or reception procedure, and/or the nineteenthidentification information indicates the DRB, and/or the twentiethidentification information indicates the third mode.

The conditions for changing the user data transmission and/or receptionmethods and/or the conditions for entering the modes of the attachcomplete state are not limited to those described above.

The C-SGN_A 95 may identify the bearer for which the user datatransmission and/or reception method is changed using the seventeenthidentification information. Identification information of the bearernewly established by the transmission and/or reception method changeprocedure may be the same as the seventeenth identification information.

The C-SGN_A 95 transmits a Modify EPS bearer context request message tothe eNB_A 45, based on the reception of the Bearer resource modificationrequest message, and/or the fifth determination (S2504). Here, theModify EPS bearer context request message may be a response message tothe Bearer resource modification request message.

The C-SGN_A 95 may include at least one or more kinds of identificationinformation among the twenty-sixth to thirty-third identificationinformation in the Modify EPS bearer context request message.

The C-SGN_A 95 may modify and/or newly create one or more kinds ofidentification information among the twenty-sixth to thirty-thirdidentification information, based on the fifth determination, andinclude the resulting identification information in the Modify EPSbearer context request message.

Specifically, the C-SGN_A 95 may include information indicating thedetermined new user data transmission and/or reception method in thetwenty-seventh identification information and/or the thirty-secondidentification information and/or the thirty-third identificationinformation, based on the fifth determination.

The C-SGN_A 95 may include information indicating a type of thedetermined new RB in the twenty-eighth identification information, basedon the fifth determination.

The C-SGN_A 95 may include information indicating a determined mode ofthe attach complete state for the C-SGN_A 95 and/or the UE_A 10 to enterafter the change in the twenty-ninth identification information, basedon the fifth determination.

The C-SGN_A 95 may change the user data transmission and/or receptionmethod, or may change the mode of the attach complete state, based onthe reception of the Bearer resource modification request message,and/or the transmission of the Modify EPS bearer context requestmessage, and/or the fifth determination.

To be more specific, the C-SGN_A 95 may change the user datatransmission and/or reception method from the method using the firsttransmission and/or reception procedure into the method using the secondtransmission and/or reception procedure, and/or change from the methodusing the second transmission and/or reception procedure into the methodusing the first transmission and/or reception procedure, or may enterthe third mode from the first mode, and/or enter the first mode from thethird mode, based on the reception of the Bearer resource modificationrequest message, and/or the transmission of the Modify EPS bearercontext request message, and/or the fifth determination.

The eNB_A 45 receives the Modify EPS bearer context request message, andtransmits an RRC message including the Modify EPS bearer context requestmessage to the UE_A 10 (S2506). Note that the RRC message may be an RRCconnection reconfiguration request message. The RRC message may be aDirect Transfer message.

The UE_A 10 receives the RRC message including the Modify EPS bearercontext request message. Furthermore, in a case that one or more kindsof identification information among the twenty-sixth to thirty-thirdidentification information are included in the Modify EPS bearer contextrequest message, the UE_A 10 acquires each piece of identificationinformation.

The UE_A 10 may recognize and determine the user data transmissionand/or reception method after the change and/or the attach completestate to enter, based on the information included in the Modify EPSbearer context request message.

For example, the UE_A 10 may recognize and determine whether the userdata transmission and/or reception method after the change is the methodusing the first transmission and/or reception procedure, or the methodusing the second transmission and/or reception procedure, based on oneor more kinds of identification information among the twenty-sixth tothirty-third identification information. In other words, the UE_A 10 mayrecognize and determine whether the attach complete state to enter isthe first mode, or the third mode, based on one or more kinds ofidentification information among the twenty-sixth to thirty-thirdidentification information. Hereinafter, the recognition anddetermination process described above is referred to as a sixthdetermination and described (S2508).

For example, the UE_A 10 may recognize the user data transmission and/orreception method after the change as the method using the firsttransmission and/or reception procedure, or may recognize the enteredattach complete state as the first mode, in a case that the Modify EPSbearer context request message includes the thirtieth identificationinformation, and/or the twenty-seventh identification information and/orthe thirty-second identification information and/or the thirty-thirdidentification information indicate the method using the firsttransmission and/or reception procedure, and/or the twenty-eighthidentification information indicates the SRB, and/or the twenty-ninthidentification information indicates the first mode, and/or thetwenty-sixth identification information is the identificationinformation identifying the SRB and/or the CRB.

Furthermore, the UE_A 10 may recognize the user data transmission and/orreception method after the change as the method using the secondtransmission and/or reception procedure, or may recognize the enteredattach complete state as the third mode, in a case that the Modify EPSbearer context request message includes the thirtieth identificationinformation, and/or the twenty-seventh identification information and/orthe thirty-second identification information and/or the thirty-thirdidentification information indicate the method using the secondtransmission and/or reception procedure, and/or the twenty-eighthidentification information indicates the DRB, and/or the twenty-ninthidentification information indicates the second mode, and/or thetwenty-sixth identification information is the identificationinformation identifying the DRB.

The conditions for recognizing the user data transmission and/orreception methods after the change, and/or the conditions forrecognizing the modes of the entered attach complete state are notlimited to those described above.

In order to respond to the received RRC message, the UE_A 10 transmitsan RRC message to the eNB_A 45 (S2510). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives the RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95, based on thereception (S2512).

The UE_A 10 transmits an RRC message including a Modify EPS bearercontext accept message to the eNB_A 45, based on the reception of theModify EPS bearer context request message (S2514). Here, the Modify EPSbearer context accept message may be a response message to the ModifyEPS bearer context request message.

Note that the RRC message to be transmitted with including the ModifyEPS bearer context accept message may be a Direct Transfer message.

The UE_A 10 may change the user data transmission and/or receptionmethod, or may change the mode of the attach complete state, based onthe reception of the Modify EPS bearer context request message, and/orthe transmission of the Modify EPS bearer context accept message, and/orthe sixth determination.

To be more specific, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 may change the user data transmission and/or reception method fromthe method using the first transmission and/or reception procedure intothe method using the second transmission and/or reception procedure,and/or change from the method using the second transmission and/orreception procedure into the method using the first transmission and/orreception procedure, or may change the mode of the attach complete statefrom the first mode into the third mode, and/or change from the thirdmode into the first mode, based on the transmission and/or reception ofthe Modify EPS bearer context request message, and/or the transmissionof the Modify EPS bearer context accept message, and/or the sixthdetermination.

The UE_A 10 and/or the eNB_A 45 may newly establish a DRB, based on thereception of the Modify EPS bearer context request message, and/or thetransmission of the Modify EPS bearer context accept message, and/or thesixth determination.

To be more specific, the UE_A 10 and/or the eNB_A 45 may establish theDRB in a case that the user data transmission and/or reception methodafter the change is the method using the second transmission and/orreception procedure, and/or the attach complete state after the enteringis the third mode.

The UE_A 10 and/or the eNB_A 45 may identify the type of the RBestablished as the Default Bearer, based on the twenty-sixthidentification information.

For example, the UE_A 10 and/or the eNB_A 45 may recognize that the SRBand/or the CRB are established as the Default Bearer in the case thatthe twenty-sixth identification information is the identificationinformation identifying the SRB and/or the CRB.

The UE_A 10 and/or the eNB_A 45 may recognize that the DRB isestablished as the Default Bearer in the case that the twenty-sixthidentification information is the identification information identifyingthe DRB.

The eNB_45 receives the RRC message including the Modify EPS bearercontext accept message, and transmits the Modify EPS bearer contextaccept message to the C-SGN_A 95 (S2516).

The C-SGN_A 95 receives the Modify EPS bearer context accept message.

By the above-described steps, the UE_A 10 and/or the C-SGN_A 95 changethe user data transmission and/or reception method, and complete thefirst transmission and/or reception method change procedure. On thecompletion of the first transmission and/or reception method changeprocedure, the UE_A 10 and/or the C-SGN_A 95 may change the mode of theattach complete state.

Note that the UE_A 10 can newly acquire the UE contexts illustrated inFIG. 21 from the core network_A 90 by the first transmission and/orreception method change procedure and store the contexts.

To be more specific, the UE_A 10 can newly acquire the UE context foreach bearer among the UE contexts illustrated in FIG. 21 from the corenetwork_A 90 by the first transmission and/or reception method changeprocedure and store the context.

Furthermore, the C-SGN_A 95 can newly acquire each of the contexts A toE illustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the first transmission and/or reception method change procedure andstore the context.

To be more specific, the C-SGN_A 95 can newly acquire the EPS bearercontext for each bearer among the contexts A to E illustrated in FIG. 19from the UE_A 10, the eNB_A 45, or the HSS_A 50 by the firsttransmission and/or reception method change procedure and store thecontext.

[1.3.3.2. Example of Second Transmission and/or Reception Method ChangeProcedure]

The example of the steps of a second transmission and/or receptionmethod change procedure will be described below using FIG. 26.

First, the C-SGN_A 95 transmits a Modify EPS bearer context requestmessage to the eNB_A 45 (S2600).

The C-SGN_A 95 may include at least one or more kinds of identificationinformation among the seventeenth to twenty-third identificationinformation in the Modify EPS bearer context request message.

The C-SGN_A 95 may transmit the Modify EPS bearer context requestmessage including one or more kinds of identification information amongthe seventeenth to twenty-third identification information to requestchange of the user data transmission and/or reception method and/or atype of the user data transmission and/or reception method after thechange.

The eNB_A 45 receives the Modify EPS bearer context request message, andtransmits an RRC message including the Modify EPS bearer context requestmessage to the UE_A 10 (S2602). Note that the RRC message may be an RRCconnection reconfiguration request message. The RRC message may be aDirect Transfer message.

The UE_A 10 receives the RRC message including the Modify EPS bearercontext request message. Furthermore, in a case that one or more kindsof identification information among the seventeenth to twenty-thirdidentification information are included in the Modify EPS bearer contextrequest message, the UE_A 10 acquires each piece of identificationinformation.

The UE_A 10 may select and determine the user data transmission and/orreception method after the change and/or the attach complete state toenter, based on the information included in the Modify EPS bearercontext request message and the identification information which theUE_A 10 has.

For example, the UE_A 10 may select and determine whether the user datatransmission and/or reception method after the change is the methodusing the first transmission and/or reception procedure, or the methodusing the second transmission and/or reception procedure, based on oneor more kinds of identification information among the first totwenty-third identification information. In other words, the UE_A 10 mayselect and determine whether the attach complete state to enter is thefirst mode, or the third mode, based on one or more kinds ofidentification information among the first to twenty-thirdidentification information. Hereinafter, the selection and determinationprocess described above is referred to as a seventh determination anddescribed (S2604).

For example, the UE_A 10 may change the user data transmission and/orreception method into the method using the first transmission and/orreception procedure, or may enter the first mode, in a case that theUE_A 10 holds the second identification information and/or the eighthidentification information and/or the tenth identification information,and/or the Modify EPS bearer context request message includes thetwenty-first identification information, and/or the eighteenthidentification information and/or the twenty-third identificationinformation indicate the method using the first transmission and/orreception procedure, and/or the nineteenth identification informationindicates the SRB, and/or the twentieth identification informationindicates the first mode.

Furthermore, the UE_A 10 may change the user data transmission and/orreception method into the method using the second transmission and/orreception procedure, or may enter the third mode, in a case that theUE_A 10 holds the third identification information and/or the ninthidentification information and/or the eleventh identificationinformation, and/or the Modify EPS bearer context request messageincludes the twenty-first identification information, and/or theeighteenth identification information and/or the twenty-thirdidentification information indicate the method using the secondtransmission and/or reception procedure, and/or the nineteenthidentification information indicates the DRB, and/or the twentiethidentification information indicates the third mode.

The conditions for changing the user data transmission and/or receptionmethods and/or the conditions for entering the modes of the attachcomplete state are not limited to those described above.

The UE_A 10 may identify the bearer for which the user data transmissionand/or reception method is changed, by using the seventeenthidentification information. Identification information of the bearernewly established by the transmission and/or reception method changeprocedure may be the same as the seventeenth identification information.

In order to respond to the received RRC message, the UE_A 10 transmitsan RRC message to the eNB_A 45 (S2606). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives the RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95, based on thereception (S2608).

The UE_A 10 transmits an RRC message including a Modify EPS bearercontext accept message to the eNB_A 45, based on the reception of theModify EPS bearer context request message, and/or the seventhdetermination (S2610). Here, the Modify EPS bearer context acceptmessage may be a response message to the Modify EPS bearer contextrequest message.

Note that the RRC message to be transmitted with including the ModifyEPS bearer context accept message may be a Direct Transfer message.

The UE_A 10 may include at least one or more kinds of identificationinformation among the twenty-sixth to thirty-third identificationinformation in the Modify EPS bearer context accept message.

The UE_A 10 may modify and/or newly create one or more kinds ofidentification information among the twenty-sixth to thirty-thirdidentification information, based on the seventh determination, andinclude the resulting identification information in the Modify EPSbearer context accept message.

Specifically, the UE_A 10 may include information indicating thedetermined new user data transmission and/or reception method in thetwenty-seventh identification information and/or the thirty-firstidentification information and/or the thirty-third identificationinformation, based on the seventh determination in the massage.

The UE_A 10 may include information indicating a type of the determinednew RB in the twenty-eighth identification information, based on theseventh determination.

The UE_A 10 may include information indicating a determined mode of theattach complete state for the UE_A 10 and/or the C-SGN_A 95 to enterafter the change in the twenty-ninth identification information, basedon the seventh determination.

The UE_A 10 may change the user data transmission and/or receptionmethod, or may change the mode of the attach complete state, based onthe reception of the Modify EPS bearer context request message, and/orthe transmission of the Modify EPS bearer context accept message, and/orthe seventh determination.

To be more specific, the UE_A 10 may change the user data transmissionand/or reception method from the method using the first transmissionand/or reception procedure into the method using the second transmissionand/or reception procedure, and/or change from the method using thesecond transmission and/or reception procedure into the method using thefirst transmission and/or reception procedure, or may enter the thirdmode from the first mode, and/or enter the first mode from the thirdmode, based on the reception of the Modify EPS bearer context requestmessage, and/or the transmission of the Modify EPS bearer context acceptmessage, and/or the seventh determination.

The UE_A 10 and/or the eNB_A 45 may newly establish a DRB, based on thereception of the Modify EPS bearer context request message, and/or thetransmission of the Modify EPS bearer context accept message, and/or theseventh determination.

To be more specific, the UE_A 10 and/or the eNB_A 45 may establish theDRB in a case that the user data transmission and/or reception methodafter the change is the method using the second transmission and/orreception procedure, and/or the attach complete state after the enteringis the third mode.

The eNB_45 receives the RRC message including the Modify EPS bearercontext accept message, and transmits the Modify EPS bearer contextaccept message to the C-SGN_A 95 (S2612).

The C-SGN_A 95 receives the Modify EPS bearer context accept message.

Furthermore, in a case that one or more kinds of identificationinformation among the twenty-sixth to thirty-third identificationinformation are included in the Modify EPS bearer context acceptmessage, the UE_A 10 acquires each piece of identification information.

The C-SGN_A 95 may recognize and determine the user data transmissionand/or reception method after the change and/or the attach completestate to enter, based on the information included in the Modify EPSbearer context accept message.

For example, the C-SGN_A 95 may recognize and determine whether the userdata transmission and/or reception method after the change is the methodusing the first transmission and/or reception procedure, or the methodusing the second transmission and/or reception procedure, based on oneor more kinds of identification information among the twenty-sixth tothirty-third identification information. In other words, the C-SGN_A 95may recognize and determine whether the attach complete state to enteris the first mode, or the third mode, based on one or more kinds ofidentification information among the twenty-sixth to thirty-thirdidentification information. Hereinafter, the recognition anddetermination process described above is referred to as an eighthdetermination and described (S2614).

For example, the C-SGN_A 95 may recognize the user data transmissionand/or reception method after the change as the method using the firsttransmission and/or reception procedure, or may recognize the enteredattach complete state as the first mode, in a case that the Modify EPSbearer context accept message includes the thirtieth identificationinformation, and/or the twenty-seventh identification information and/orthe thirty-first identification information and/or the thirty-thirdidentification information indicate the method using the firsttransmission and/or reception procedure, and/or the twenty-eighthidentification information indicates the SRB, and/or the twenty-ninthidentification information indicates the first mode, and/or thetwenty-sixth identification information is the identificationinformation identifying the SRB and/or the CRB.

Furthermore, the C-SGN_A 95 may recognize the user data transmissionand/or reception method after the change as the method using the secondtransmission and/or reception procedure, or may recognize the enteredattach complete state as the third mode, in a case that the Modify EPSbearer context accept message includes the thirtieth identificationinformation, and/or the twenty-seventh identification information and/orthe thirty-first identification information and/or the thirty-thirdidentification information indicate the method using the secondtransmission and/or reception procedure, and/or the twenty-eighthidentification information indicates the DRB, and/or the twenty-ninthidentification information indicates the second mode, and/or thetwenty-sixth identification information is the identificationinformation identifying the DRB.

The conditions for recognizing the user data transmission and/orreception methods after the change, and/or the conditions forrecognizing the modes of the entered attach complete state are notlimited to those described above.

The C-SGN_A 95 may change the user data transmission and/or receptionmethod, or may change the mode of the attach complete state, based onthe reception of the Modify EPS bearer context accept message, and/orthe eighth determination.

To be more specific, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 may change the user data transmission and/or reception method fromthe method using the first transmission and/or reception procedure intothe method using the second transmission and/or reception procedure,and/or change from the method using the second transmission and/orreception procedure into the method using the first transmission and/orreception procedure, or may change the mode of the attach complete statefrom the first mode into the third mode, and/or change from the thirdmode into the first mode, based on the transmission and/or reception ofthe Modify EPS bearer context accept message, and/or the eighthdetermination.

The UE_A 10 and/or the eNB_A 45 may identify the type of the RBestablished as the Default Bearer, based on the twenty-sixthidentification information.

For example, the UE_A 10 and/or the eNB_A 45 may recognize that the SRBand/or the CRB are established as the Default Bearer in the case thatthe twenty-sixth identification information is the identificationinformation identifying the SRB and/or the CRB.

The UE_A 10 and/or the eNB_A 45 may recognize that the DRB isestablished as the Default Bearer in the case that the twenty-sixthidentification information is the identification information identifyingthe DRB.

By the above-described steps, the UE_A 10 and/or the C-SGN_A 95 changethe user data transmission and/or reception method, and complete thesecond transmission and/or reception method change procedure. On thecompletion of the second transmission and/or reception method changeprocedure, the UE_A 10 and/or the C-SGN_A 95 may change the mode of theattach complete state.

Note that the UE_A 10 can newly acquire the UE contexts illustrated inFIG. 21 from the core network_A 90 by the second transmission and/orreception method change procedure and store the contexts.

To be more specific, the UE_A 10 can newly acquire the UE context foreach bearer among the UE contexts illustrated in FIG. 21 from the corenetwork_A 90 by the second transmission and/or reception method changeprocedure and store the context.

Furthermore, the C-SGN_A 95 can newly acquire each of the contexts A toE illustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the second transmission and/or reception method change procedure andstore the context.

To be more specific, the C-SGN_A 95 can newly acquire the EPS bearercontext for each bearer among the contexts A to E illustrated in FIG. 19from the UE_A 10, the eNB_A 45, or the HSS_A 50 by the secondtransmission and/or reception method change procedure and store thecontext.

[1.3.3.3. Example of Third Transmission and/or Reception Method ChangeProcedure]

The example of the steps of a third transmission and/or reception methodchange procedure will be described below using FIG. 27.

First, the C-SGN_A 95 transmits a Deactivate EPS bearer context requestmessage to the eNB_A 45 (S2700).

The C-SGN_A 95 may include at least one or more kinds of identificationinformation among the seventeenth to twenty-fifth identificationinformation in the Deactivate EPS bearer context request message.

The C-SGN_A 95 may transmit the Deactivate EPS bearer context requestmessage including one or more kinds of identification information amongthe seventeenth to twenty-fifth identification information to requestchange of the user data transmission and/or reception method and/or atype of the user data transmission and/or reception method after thechange.

In other words, the C-SGN_A 95 may transmit the Deactivate EPS bearercontext request message including one or more kinds of identificationinformation among the seventeenth to twenty-fifth identificationinformation to request re-establishment of the PDN connection and/orDefault Bearer, and/or a type of the user data transmission and/orreception method after the re-establishment.

The eNB_A 45 receives the Deactivate EPS bearer context request message,and transmits an RRC message including the Deactivate EPS bearer contextrequest message to the UE_A 10 (S2702). Note that the RRC message may bean RRC connection reconfiguration request message. The RRC message maybe a Direct Transfer message.

The UE_A 10 receives the RRC message including the Deactivate EPS bearercontext request message. Furthermore, in a case that one or more kindsof identification information among the seventeenth to twenty-fifthidentification information are included in the Deactivate EPS bearercontext request message, the UE_A 10 acquires each piece ofidentification information.

The UE_A 10 may select and determine whether or not the re-establishmentof the PDN connection and/or Default Bearer is necessary, and/or theuser data transmission and/or reception method after there-establishment, and/or the attach complete state to enter, based onthe information included in the Deactivate EPS bearer context requestmessage and/or the identification information which the UE_A 10 has.

For example, the UE_A 10 may select and determine whether or not there-establishment of the PDN connection and/or Default Bearer isnecessary, and/or whether the user data transmission and/or receptionmethod after the re-establishment is the method using the firsttransmission and/or reception procedure, or the method using the secondtransmission and/or reception procedure, based on one or more kinds ofidentification information among the first to twenty-fifthidentification information. In other words, the UE_A 10 may select anddetermine whether the attach complete state to enter is the first modeand/or the second mode or the third mode and/or the fourth mode, basedon one or more kinds of identification information among the first totwenty-fifth identification information. Hereinafter, the selection anddetermination process described above is referred to as a ninthdetermination and described (S2704).

For example, the UE_A 10 may establish, after disconnecting theestablished PDN connection and/or Default Bearer, the PDN connectionand/or Default Bearer for transmitting and/or receiving the user data inthe method using the first transmission and/or reception procedure, in acase that the UE_A 10 holds the second identification information and/orthe eighth identification information and/or the tenth identificationinformation, and/or the Deactivate EPS bearer context request messageincludes the twenty-first identification information and/or thetwenty-fourth identification information and/or the twenty-fifthidentification information, and/or the eighteenth identificationinformation and/or the twenty-third identification information indicatesthe method using the first transmission and/or reception procedure,and/or the nineteenth identification information indicates the SRB,and/or the twentieth identification information indicates the firstmode.

In other words, in this case, the UE_A 10 may disconnect the establishedPDN connection and/or Default Bearer to enter the second mode, andthereafter, may perform the PDN connectivity procedure to enter thefirst mode.

Furthermore, the UE_A 10 may establish, after disconnecting theestablished PDN connection and/or Default Bearer, the PDN connectionand/or Default Bearer for transmitting and/or receiving the user data inthe method using the second transmission and/or reception procedure, ina case that the UE_A 10 holds the third identification informationand/or the ninth identification information and/or the eleventhidentification information, and/or the Deactivate EPS bearer contextrequest message includes the twenty-first identification informationand/or the twenty-fourth identification information and/or thetwenty-fifth identification information, and/or the eighteenthidentification information and/or the twenty-third identificationinformation indicates the method using the second transmission and/orreception procedure, and/or the nineteenth identification informationindicates the DRB, and/or the twentieth identification informationindicates the third mode.

In other words, in this case, the UE_A 10 may disconnect the establishedPDN connection and/or Default Bearer to enter the fourth mode, andthereafter, may perform the PDN connectivity procedure to enter thethird mode.

The conditions for re-establishing the PDN connection and/or the DefaultBearer, and/or the conditions for changing the user data transmissionand/or reception methods, and/or the conditions for entering the modesof the attach complete state are not limited to those described above.

The UE_A 10 may identify the bearer for which the user data transmissionand/or reception method is changed, by using the seventeenthidentification information. In other words, the UE_A 10 may identify thebearer to disconnect and/or re-establish, by using the seventeenthidentification information.

Identification information of the bearer established by the new PDNconnectivity procedure may be the same as the seventeenth identificationinformation.

In order to respond to the received RRC message, the UE_A 10 transmitsan RRC message to the eNB_A 45 (S2706). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives the RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95 based on thereception (S2708).

The UE_A 10 transmits an RRC message including a Deactivate EPS bearercontext accept message to the eNB_A 45, based on the reception of theDeactivate EPS bearer context request message, and/or the ninthdetermination (S2710). Here, the Deactivate EPS bearer context acceptmessage may be a response message to the Deactivate EPS bearer contextrequest message.

Note that the RRC message to be transmitted with including theDeactivate EPS bearer context accept message may be a Direct Transfermessage.

The UE_A 10 may include at least the twenty-sixth identificationinformation in the Deactivate EPS bearer context accept message.

The UE_A 10 may change the mode of the attach complete state, based onthe reception of the Deactivate EPS bearer context request message,and/or the transmission of the Deactivate EPS bearer context acceptmessage, and/or the ninth determination.

To be more specific, the UE_A 10 may enter the third mode from the firstmode, and/or enter the first mode from the third mode, based on thereception of the Deactivate EPS bearer context request message, and/orthe transmission of the Deactivate EPS bearer context accept message,and/or the ninth determination.

The eNB_45 receives the RRC message including the Deactivate EPS bearercontext accept message, and transmits the Deactivate EPS bearer contextaccept message to the C-SGN_A 95 (S2712).

The C-SGN_A 95 receives the Deactivate EPS bearer context acceptmessage.

Furthermore, in a case that the twenty-sixth identification informationis included in the Deactivate EPS bearer context accept message, theUE_A 10 acquires the twenty-sixth identification information.

The C-SGN_A 95 may change the mode of the attach complete state, basedon the reception of the Deactivate EPS bearer context accept message,and/or the ninth determination.

To be more specific, the C-SGN_A 95 may enter the fourth mode from thefirst mode, and/or enter the second mode from the third mode, based onthe reception of the Deactivate EPS bearer context accept message,and/or the ninth determination.

The UE_A 10 may transmit the PDN connectivity request message to theC-SGN_A 95, based on the reception of the Deactivate EPS bearer contextrequest message, and/or the transmission of the Deactivate EPS bearercontext accept message, and/or the ninth determination. Note that theUE_A 10 may transmit the PDN connectivity request message to the eNB_A45, and the transmitted PDN connectivity request message may betransferred to the C-SGN_A 95 via the eNB 45.

The UE_A 10 may transmit the PDN connectivity request message includingone or more kinds of identification information among the first to fifthidentification information, based on the ninth determination, to requesta type of the PDN connection to establish, and/or a mode of the attachcomplete state to enter, and/or a type of the user data transmissionand/or reception method.

As describe above, the UE_A 10 may perform a PDN connectivity procedurefor re-establishing the PDN connection and/or the Default Bearer, basedon the reception of the Deactivate EPS bearer context request message,and/or the transmission of the Deactivate EPS bearer context acceptmessage, and/or the ninth determination (S2714).

The PDN connectivity procedure for re-establishing the PDN connectionand/or the Default Bearer may be the same as the procedure described inthe section 1.3.2, and therefore detailed description thereof will beomitted.

The UE_A 10 and/or the C-SGN_A 95 may change the user data transmissionand/or reception method, or may change the mode of the attach completestate, based on the transmission and/or reception of the Deactivate EPSbearer context accept message, and/or the ninth determination, and/orthe completion of the PDN connectivity procedure.

To be more specific, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 may change the user data transmission and/or reception method fromthe method using the first transmission and/or reception procedure intothe method using the second transmission and/or reception procedure,and/or change from the method using the second transmission and/orreception procedure into the method using the first transmission and/orreception procedure, or may change the mode of the attach complete statefrom the first mode and/or the second mode and/or the fourth mode intothe third mode, and/or change from the fourth mode and/or the third modeand/or the second mode into the first mode, based on the transmissionand/or reception of the Deactivate EPS bearer context accept message,and/or the ninth determination, and/or the completion of the PDNconnectivity procedure.

The UE_A 10 and/or the eNB_A 45 may identify the type of the RBestablished as the Default Bearer, based on the sixteenth identificationinformation.

For example, the UE_A 10 and/or the eNB_A 45 may recognize that the SRBand/or the CRB are established as the Default Bearer in the case thatthe sixteenth identification information is the identificationinformation identifying the SRB and/or the CRB.

The UE_A 10 and/or the eNB_A 45 may recognize that the DRB isestablished as the Default Bearer in the case that the sixteenthidentification information is the identification information identifyingthe DRB.

By the above-described steps, the UE_A 10 and/or the C-SGN_A 95 changethe user data transmission and/or reception method, and complete thethird transmission and/or reception method change procedure. On thecompletion of the third transmission and/or reception method changeprocedure, the UE_A 10 and/or the C-SGN_A 95 may change the mode of theattach complete state.

Note that the UE_A 10 can newly acquire the UE contexts illustrated inFIG. 21 from the core network_A 90 by the third transmission and/orreception method change procedure and store the contexts.

To be more specific, the UE_A 10 can newly acquire the UE context foreach bearer among the UE contexts illustrated in FIG. 21 from the corenetwork_A 90 by the third transmission and/or reception method changeprocedure and store the context.

Furthermore, the C-SGN_A 95 can newly acquire each of the contexts A toE illustrated in FIG. 19 from the UE_A 10, the eNB_A 45, or the HSS_A 50by the third transmission and/or reception method change procedure andstore the context.

To be more specific, the C-SGN_A 95 can newly acquire the EPS bearercontext for each bearer among the contexts A to E illustrated in FIG. 19from the UE_A 10, the eNB_A 45, or the HSS_A 50 by the thirdtransmission and/or reception method change procedure and store thecontext.

[1.3.3.4. Modification Example of Transmission and/or Reception MethodChange Procedure]

Although the transmission and/or reception method change procedure isdescribed in a case that the core network_A 90 in the transmissionand/or reception method change procedure example described above is acore network configured by including the C-SGN_A 95 described usingFIGS. 3A and 3B, the core network_A 90 may be a core network configuredby including the PGW_A 30, the SGW_A 35, the MME_A 40, or the like asdescribed using FIGS. 2A and 2B.

In this case, the NAS message such as the Bearer resource modificationrequest message, the Modify EPS bearer context accept message, theDeactivate EPS bearer context accept message transmitted by the UE_A 10described in this procedure is received by the MME 45, not by theC-SGN_A 95.

Accordingly, the reception and processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and processes of the NAS message such asthe Modify EPS bearer context request message, the Deactivate EPS bearercontext request message by the C-SGN_A 95 in the above description canbe replaced with those performed by the MME_A 40.

[1.3.4. Example of UL User Data Transmission and/or Reception Procedure]

Next, steps in which the UE_A 10 which connects to the network transmitsUL user data will be described.

Hereinafter, transmission steps of the UL user data will be described.

The UE_A 10 transmits a first message to the eNB_A 45. The first messageis a message for requesting at least transmission timing information andresource assignment information, and the UE_A 10 transmits the firstmessage at least including a randomly selected preamble to the eNB_A 45.

Note that the first message is a control signal of a Physical layer, maybe a Random Access Channel (RACH) Preamble message of Message 1. Thefirst message may be transmitted using a Physical Random Access Channel(PRACH).

The eNB_A 45 receives the first message, and transmits a second messageto the UE_A 10 as a response to the first message. The second message istransmitted with including at least the transmission timing informationand the resource assignment information. To be more specific, thetransmission timing information may be a Timing Advance, and theresource assignment information may be a UL Grant. The second message isa control signal in a Media Access Control (MAC) layer, and may betransmitted using a Medium Access Control Random Access Response (MACRAR).

Note that the second message may be a RACH Response message of a Message2.

A communication procedure after the UE_A 10 receives the second messagecan branch into a first transmission and/or reception procedure example,a second transmission and/or reception procedure example, a thirdtransmission and/or reception procedure example, which will be describedlater.

The UE_A 10 may branch the communication procedure into the firsttransmission and/or reception procedure example and/or the secondtransmission and/or reception procedure example and/or the thirdtransmission and/or reception procedure example, based on the secondand/or fourth determination.

[1.3.4.1. Description of First Transmission and/or Reception ProcedureExample]

The first transmission and/or reception procedure example is a procedurein which the UE_A 10 transmits and/or receives the user data withoutestablishing the DRB. In other words, the first transmission and/orreception procedure example is a procedure for transmitting the userdata by use of a radio bearer for transmitting and/or receiving thecontrol message.

In other words, the first transmission and/or reception procedureexample is a procedure for the UE_A 10 and the C-SGN_A 95 to transmitand/or receive the user data by use of an EPS bearer including the SRB.Furthermore, in other words, the first transmission and/or receptionprocedure example is a procedure in which the UE_A 10 transmits and/orreceives the user data by use of the SRB.

Hereinafter, the first transmission and/or reception procedure examplewill be described in detail using FIG. 28.

The UE_A 10 transmits a third message to the eNB_A 45, based on thereception of the second message from the eNB_A 45 (S2800).

The eNB_A 45 receives the third message transmitted by the UE_A 10. TheeNB_A 45 transmits a fourth message to the UE_A 10, based on thereception of the third message (S2802).

The UE_A 10 transmits the fourth message transmitted by the eNB_A 45.The UE_A 10 transmits a fifth message to the eNB_A 45, based on thereception of the fourth message (S2804).

The UE_A 10 may transmit the NAS message including the UL user data withbeing included in the third message and/or the fifth message. Note thatthe UE_A 10 may encrypt and transmit the UL user data or the NAS messageincluding the UL user data.

The eNB_A 45 receives the NAS message including the UL user data, basedon the reception of the third message and/or fifth message.

The eNB_A 45 may transmit an Initial UE message of an S1 ApplicationProtocol (S1AP) to the C-SGN_A 95, based on the reception of the NASmessage including the UL user data (S2806).

The eNB_A 45 may transmit the Initial UE message of the S1AP includingat least the NAS message including the UL user data.

The eNB_A 45 may transmit a completion message to the UE_A 10, based onthe reception of the third message and/or the fifth message, and/or thetransmission of the Initial UE message of the S1AP (S2808).

The UE_A 10 receives the completion message transmitted by the eNB_A 45.

The C-SGN_A 95 receives the Initial UE message of the S1AP transmittedby the eNB_A 45, and/or the NAS message including the UL user dataincluded in the Initial UE message of the S1AP.

The C-SGN_A 95 decodes the received NAS message, and/or extracts theuser data included in the received NAS message, based on the receptionof the NAS message including the UL user data included in the Initial UEmessage of the S1AP (S2810). The C-SGN_A 95 may decode the extracteduser data, as needed.

The C-SGN_A 95 transmits the user data to the PDN_A 5, based on theextraction and/or decode of the user data included in the NAS message(S2812). The C-SGN_A 95 may decode the user data and then transmit thedecoded user data to the PDN_A 5.

By the above-described procedures, the UE_A 10 can transmit a small datapacket being the UL user data to the PDN_A 5 without establishing theDRB. Furthermore, after the completion of the first transmission and/orreception procedure example, the UE_A 10 can enter the idle state, ormaintain the idle state.

In a case that a size of the user data to be transmitted and/or receivedis large, the UE_A 10 and/or the C-SGN_A 95 may not transmit and/orreceive the user data by the first transmission and/or receptionprocedure, but may transmit the user data by use of the secondtransmission and/or reception procedure.

[1.3.4.2. Description of Second Transmission and/or Reception ProcedureExample]

The second transmission and/or reception procedure example is aprocedure in which the UE_A 10 transmits and/or receives the user dataafter establishing the DRB.

In other words, the second transmission and/or reception procedureexample is a procedure for the UE_A 10 and the C-SGN_A 95 to transmitand/or receive the user data by use of an EPS bearer including the DRB.Furthermore, in other words, the second transmission and/or receptionprocedure example is a procedure in which the UE_A 10 transmits and/orreceives the user data by use of the DRB.

Hereinafter, the second transmission and/or reception procedure examplewill be described in detail using FIG. 5.

The UE_A 10 transmits a third message to the eNB_A 45, based on thereception of the second message from the eNB_A 45 (S2900).

The UE_A 10 may transmit the third message including at least the NASmessage and/or a Resume ID.

The NAS message may be a message for re-establishing the DRB.

The Resume ID may be identification information identifying the DRB tore-establish. And/or, the Resume ID may be identification informationidentifying a context corresponding to the DRB to re-establish which isheld by the eNB_A 45. And/or, the Resume ID may be identificationinformation indicating that a CIoT terminal in an active state is to beput in the idle state. And/or, the Resume ID may be identificationinformation indicating that a CIoT terminal in the idle state is to beput in the active state.

For example, the eNB_A 45 may transmit the Resume ID to the UE_A 10 toenter the idle state from the active state. Moreover, the UE_A 10 mayreceive the Resume ID from the eNB_A 45 to enter the idle state from theactive state.

The UE_A 10 may transmit the received Resume ID to the eNB_A 45 to enterthe active state from the idle state. Moreover, the eNB_A 45 may receivethe Resume ID from the UE_A 10 to enter the active state from the idlestate.

By using the same Resume ID as the Resume ID transmitted and/or receivedfor entering the idle state from the active state and the Resume IDtransmitted and/or received for entering the active state from the idlestate, the context used in the previous active state can be identified,and the UE_A 10 and the eNB_A 45 can return to the same communicationstate as in the previous active state to re-establish the DRB based onthe identified context, or the like.

In this way, the UE_A 10 and the eNB_A 45 can transit between the activestate and idle state, based on the Resume ID. The eNB_A 45 receives thethird message transmitted by the UE_A 10. The eNB_A 45 receives the NASmessage and/or the Resume ID, based on the reception of the thirdmessage.

The eNB_A 45 re-establishes the DRB identified by the Resume ID, basedon the reception of the Resume ID included in the third message.

The eNB_A 45 transmits a fourth message to the UE_A 10, based on thereception of the third message and/or the re-establishment of the DRBidentified by the Resume ID (S2902).

The eNB_A 45 may transmit the fourth message including at least theResume ID for identifying the re-established DRB.

The eNB_A 45 makes the state of the eNB_A 45 enter the active mode,based on the reception of the third message, and/or the reception of theNAS message, and/or the re-establishment of the DRB identified by theResume ID, and/or the transmission of the fourth message.

The eNB_A 45 transmits a UE context activation message of the S1Application Protocol (S1AP) to the C-SGN_A 95, based on the reception ofthe third message, and/or the reception of the NAS message, and/or there-establishment of the DRB identified by the Resume ID, and/or thetransmission of the fourth message, and/or change of the state of theeNB_A 45 into the active mode (S2904). The eNB_A 45 may transmit the UEcontext activation message of the S1AP including the NAS message.

The C-SGN_A 95 receives the UE context activation message of the S1AP.The C-SGN_A 95 makes the state of the C-SGN_A 95 enter the active mode,based on the reception of the UE context activation message of the S1AP.The C-SGN_A 95 transmits a UE context activation response message of theS1AP to the eNB_A 45, based on the reception of the UE contextactivation message of the S1AP, and/or the reception of the NAS message,and/or change of the state of the C-SGN_A 95 into the active mode(S2906).

The UE_A 10 receives the fourth message transmitted by the eNB_A 45. TheUE_A 10 makes the state of the UE_A 10 enter the active mode, based onthe reception of the fourth message, and/or the reception of the ResumeID for identifying the re-established DRB included in the fourthmessage.

The UE_A 10 transmits the UL user data to the PDN_A 5 via the eNB_A 45and/or the C-SGN_A 95, based on the reception of the fourth message,and/or the reception of the Resume ID for identifying the re-establishedDRB included in the fourth message, and/or change of the state of theUE_A 10 into the active mode (S2908) (S2910) (S2912).

The UE_A 10 continues to transmit the UL user data to the PDN_A 5 viathe eNB_A 45 and/or the C-SGN_A 95 so long as the UL user data to betransmitted is present. Presence or absence of the data to betransmitted may be determined from a data residual amount of the bufferwhich accumulates the UL user data to be transmitted or the like.

By the above-described procedures, the UE_A 10 can transmit the UL userdata. Furthermore, the UE_A 10 can also receive DownLink (DL) user datausing the above-described procedures. Note that the DL user data can betransmitted from the PDN_A 5, and can be received via the C-SGN_A 95 andthe eNB_A 45.

The eNB_A 45 transfers the UL user data received from the UE_A 10 to theC-SGN_A 95.

In a case that the eNB_A 45 detects no reception of the UL user data fora certain time period, the eNB_A 45 starts a procedure for making thestates of the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 enterthe idle mode as illustrated in (A) of FIG. 5. In other words, the eNB_A45 dose not perform the procedure as illustrated in (A) of FIG. 5 solong as the eNB_A 45 continues to receive the UL user data.

The eNB_A 45 transmits a UE context deactivation message of the S1AP tothe C-SGN_A 95, based on the detection of no reception of the UL userdata for a certain time period (S2914).

The C-SGN_A 95 receives the UE context deactivation message of the S1AP.The C-SGN_A 95 makes the state of the C-SGN_A 95 enter the idle mode,based on the reception of the UE context deactivation message of theS1AP. The C-SGN_A 95 transmits the UE context deactivation responsemessage of the S1AP to the eNB_A 45, based on the reception of the UEcontext deactivation message of the S1AP and/or change of the state ofthe C-SGN_A 95 into the idle mode (S2916).

The eNB_A 45 transmits an RRC Connection Suspend message to the UE_A 10,based on the transmission of the UE context deactivation message and/orthe reception of the UE context deactivation response (S2918).

The eNB_A 45 may transmit the RRC Connection Suspend message includingat least the Resume ID.

Here, the Resume ID may be identification information identifying theDRB to disconnect. To be more specific, the Resume ID may beidentification information identifying the context corresponding to theDRB to disconnect which is held by the UE_A 10 and/or the eNB_A 45.

The eNB_A 45 disconnects the DRB identified by the Resume ID, based onthe transmission of the RRC Connection Suspend message including theResume ID. The eNB_A 45 performs the disconnection of the DRB identifiedby the Resume ID, but may continue to keep the context corresponding tothe disconnected DRB without deleting the context.

The eNB_A 45 makes the state of the eNB_A 45 enter the idle mode, basedon the disconnection of the DRB identified by the Resume ID.

The UE_A 10 receives the RRC Connection Suspend message transmitted bythe eNB_A 45.

The UE_A 10 disconnects the DRB identified by the Resume ID, based onthe reception of the RRC Connection Suspend message and/or the receptionof Resume ID included in the RRC Connection Suspend message. The UE_A 10performs the disconnection of the DRB identified by the Resume ID, butmay continue to keep the context corresponding to the disconnected DRBwithout deleting the context.

The UE_A 10 makes the state of the UE_A 10 enter the idle mode, based onthe disconnection of the DRB identified by the Resume ID.

By the above-described procedures, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 can disconnect the DRB to enter the idle modewhile keeping the contexts of UE_A 10 and/or the eNB_A 45.

[1.3.4.3. Description of Third Transmission and/or Reception ProcedureExample]

The third transmission and/or reception procedure example is atransmission and/or reception procedure of the related art.

The third transmission and/or reception procedure example is a procedurein which the UE_A 10 transmits and/or receives the user data afterestablishing the DRB.

The third transmission and/or reception procedure may be the sameprocedure as the second transmission and/or reception procedure.Therefore, detailed description of the procedure will be omitted here.

However, in the case of the third transmission and/or receptionprocedure, the UE_A 10 may transmit a fifth message including the NASmessage without including the NAS message and/or Resume ID in the thirdmessage.

Furthermore, the message of the S1AP transmitted and/or received betweenthe eNB_A 45 and the C-SGN_A 95 is not limited to the UE contextactivation message and/or the UE context activation response message andmay be those transmitting and/or receiving the NAS message.

The UE_A 10 may transmit the UL user data, based on reception of aresponse message to the fifth message.

In the case of the third transmission and/or reception procedure, theUE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may create a newcontext to establish the DRB or enter the active state, without usingthe context used in the previous active state.

The UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may transmitand/or receive the UE context deactivation message and/or RRC connectiondeactivation message not including the Resume ID.

The UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 may transmitand/or receive the UE context deactivation message and/or RRC connectiondeactivation message not including the Resume ID to enter the idle modeas in the related art.

[1.3.4.4. Modification Example of UL User Data Transmission and/orReception Procedure]

Although the attach procedure is described in a case that the corenetwork_A 90 in the UL user data transmission and/or reception procedureexample described above is a core network configured by including theC-SGN_A 95 described using FIGS. 3A and 3B, the core network_A 90 may bea core network configured by including the PGW_A 30, the SGW_A 35, theMME_A 40, or the like as described using FIGS. 2A and 2B.

In this case, the NAS message transmitted by the UE_A 10 described inthis procedure is received by the MME 45, not by the C-SGN_A 95.

Accordingly, the reception and processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

2. Modification Example

A program running on each of the apparatuses according to the presentinvention may be a program that controls a Central Processing Unit (CPU)and the like to cause a computer to operate in such a manner as toimplement functionalities according to the embodiment of the presentinvention. A program or information handled by the program istransitorily stored in a volatile memory such as a Random Access Memory(RAM), a non-volatile memory such as a flash memory, a Hard Disk Drive(HDD), or other storage device systems.

The program for implementing the functionalities according theembodiment of the present invention may be recorded on acomputer-readable recording medium. The functionalities may beimplemented by causing a computer system to read the program recorded onthis recording medium for execution. Note that it is assumed that the“computer system” refers to a computer system built into each apparatus,and the computer system includes an operating system and hardwarecomponents such as a peripheral device. The “computer-readable recordingmedium” may include a semiconductor recording medium, an opticalrecording medium, a magnetic recording medium, a medium dynamicallyholding a program for a short time, or other computer-readable recordingmedia.

The respective functional blocks or features of the apparatuses used inthe above-described embodiment may be installed or performed by anelectrical circuit, for example, an integrated circuit or multipleintegrated circuits. The electrical circuit designed to perform thefunctionalities described in this specification may include ageneral-purpose processor, a digital signal processor (DSP), anapplication specific integrated circuit (ASIC), a field programmablegate array signal (FPGA), or other programmable logic devices, discretegates or transistor logic, discrete hardware components, or combinationsthereof. The general-purpose processor may be a microprocessor, or maybe a processor of a known type, a controller, a micro-controller, or astate machine. The electrical circuit described above may includedigital circuits, or analog circuits. Furthermore, in a case that withadvances in semiconductor technology, a circuit integration technologywith which the current integrated circuit is replaced appears, thepresent invention can also use a new integrated circuit based on therelevant technology.

It is to be noted that the invention of the present patent applicationis not limited to the above-described embodiments. Furthermore, anexample of the apparatuses has described in the embodiment, but thepresent invention is not limited to such an apparatus and is applicableto a terminal apparatus or a communication device of a fixed-type or astationary-type electronic apparatus installed indoors or outdoors, forexample, such as an Audio-Video (AV) apparatus, a kitchen apparatus, acleaning or washing machine, an air-conditioning apparatus, officeequipment, a vending machine, and other household apparatuses.

The embodiments of the present invention have been described in detailabove referring to the drawings, but the specific configuration is notlimited to the embodiment and includes, for example, an amendment to adesign that falls within the scope that does not depart from the gist ofthe present invention. Furthermore, various modifications are possiblewithin the scope of the present invention defined by claims, andembodiments that are made by suitably combining technical meansdisclosed according to the different embodiments are also included inthe technical scope of the present invention. Furthermore, aconfiguration in which a constituent element that achieves the sameeffect is substituted for the one that is described according to theembodiments is also included in the technical scope of the presentinvention.

REFERENCE SIGNS LIST

-   1 Communication system-   5 PDN_A-   10 UE_A-   20 UTRAN_A-   22 eNB (UTRAN)_A-   24 RNC_A-   25 GERAN_A-   26 BSS_A-   30 PGW_A-   35 SGW_A-   40 MME_A-   45 eNB_A-   50 HSS_A-   55 AAA_A-   60 PCRF_A-   65 ePDG_A-   70 WLAN ANa-   72 WLAN APa-   74 TWAG_A-   75 WLAN ANb-   76 WLAN APb-   80 LTE AN_A-   90 Core network_A-   95 C-SGN_A-   100 CIOT AN_A

The invention claimed is:
 1. A User Equipment (UE) comprising: acontroller; and transmission and reception circuitry, wherein thetransmission and reception circuitry is configured to: perform acommunication by use of a control plane Cellular Internet of Things(CIoT) Evolved Packet System (EPS) Optimisation, based on completion ofan attach procedure, transmit a first control message to a core networkduring the communication by use of the control plane CIoT EPSOptimisation, the first control message including a flag for indicatingthat radio bearers establishment is requested, receive, from the corenetwork, a second control message as a response to the first controlmessage, and perform the communication by use of the radio bearers,based on reception of the second control message, the transmission andreception circuitry, in the attach procedure, is configured to: transmitan ATTACH REQUEST message to the core network, receive an ATTACH ACCEPTmessage from the core network, and transmit an ATTACH COMPLETE messageto the core network, wherein the ATTACH REQUEST message includes UEcapability information for indicating support of the control plane CIoTEPS Optimisation and information for a request to use the control planeCIoT EPS Optimisation, and the ATTACH ACCEPT message includes networkcapability information for indicating support of the control plane CIoTEPS Optimisation, and the controller is configured to receive thenetwork capability information for indicating the support of the controlplane CIoT EPS Optimisation to recognize that use of the communicationby use of the control plane CIoT EPS Optimisation is accepted.
 2. The UEaccording to claim 1, wherein the second control message includesinformation on an Evolved Packet System (EPS) bearer.
 3. The UEaccording to claim 1, wherein the communication by use of the controlplane CIoT EPS Optimisation is a communication of user data using acommunication path for transmitting and/or receiving a control message,and is performed through the core network, the communication by use ofthe radio bearers is a communication of user data using a communicationpath for transmitting and/or receiving the user data.
 4. A MobilityManagement Entity (MME) comprising: a controller; and transmission andreception circuitry, wherein the transmission and reception circuitry isconfigured to: perform a communication by use of a control planeCellular Internet of Things (CIoT) Evolved Packet System (EPS)Optimisation, based on completion of an attach procedure, and in a casethat a first control message is received from a User Equipment (UE)during the communication by use of the control plane CIoT EPSOptimisation, transmit, to the UE, a second control message as aresponse to the first control message, the first control messageincluding a flag for indicating that radio bearers establishment isrequested, the transmission and reception circuitry, in the attachprocedure, is configured to: receive an ATTACH REQUEST message from theUE, transmit an ATTACH ACCEPT message to the UE, and receive an ATTACHCOMPLETE message from the UE, wherein the ATTACH REQUEST messageincludes UE capability information indicating support of the controlplane CIoT EPS Optimisation and information for a request to use thecontrol plane CIoT EPS Optimisation, and the ATTACH ACCEPT messageincludes network capability information for indicating support of thecontrol plane CIoT EPS Optimisation, the network capability informationfor indicating the support of the control plane CIoT EPS Optimisation isused by the UE to recognize that use of the communication by use of thecontrol plane CIoT EPS Optimisation is accepted, and after the secondcontrol message is transmitted, the communication by use of the radiobearers is performed.
 5. The MME according to claim 4, wherein thesecond control message includes information on an Evolved Packet System(EPS) bearer.
 6. The MME according to claim 4, wherein the communicationby use of the control plane CIoT EPS Optimisation is a communication ofuser data using a communication path for transmitting and/or receiving acontrol message, and is performed via the MME, the communication by useof the radio bearers is a communication of user data using acommunication path for transmitting and/or receiving the user data.
 7. Acommunication method performed by a User Equipment (UE), thecommunication method comprising the steps of: performing a communicationby use of a control plane Cellular Internet of Things (CIoT) EvolvedPacket System (EPS) Optimisation, based on completion of an attachprocedure; transmitting a first control message to a core network duringthe communication by use of the control plane CIoT EPS Optimisation, thefirst control message including a flag for indicating that radio bearersestablishment is requested; receiving, from the core network, a secondcontrol message as a response to the first control message; andperforming the communication by use of the radio bearers, based onreception of the second control message, wherein in the attachprocedure, an ATTACH REQUEST message is transmitted to the core network,an ATTACH ACCEPT message is received from the core network, and anATTACH COMPLETE message is transmitted to the core network, wherein theATTACH REQUEST message includes UE capability information for indicatingsupport of the control plane CIoT EPS Optimisation and information for arequest to use the control plane CIoT EPS Optimisation, and the ATTACHACCEPT message includes network capability information indicatingsupport of the control plane CIoT EPS Optimisation, and by receiving thenetwork capability information for indicating the support of the controlplane CIoT EPS Optimisation, the UE recognizes that use of thecommunication by use of the control plane CIoT EPS Optimisation isaccepted.
 8. The communication method performed by the UE according toclaim 7, wherein the second control message includes information on anEvolved Packet System (EPS) bearer.
 9. The communication methodperformed by the UE according to claim 7, wherein the communication byuse of the control plane CIoT EPS Optimisation is a communication ofuser data using a communication path for transmitting and/or receiving acontrol message, and is performed through the core network, thecommunication by use of the radio bearers is a communication of userdata using a communication path for transmitting and/or receiving theuser data.
 10. A communication method performed by a Mobility ManagementEntity (MME), the communication method comprising the steps of:performing a communication by use of a control plane Cellular Internetof Things (CIoT) Evolved Packet System (EPS) Optimisation, based oncompletion of an attach procedure; and in a case that a first controlmessage is received from a User Equipment (UE) during the communicationby use of the control plane CIoT EPS Optimisation, transmitting, to theUE, a second control message as a response to the first control message,the first control message including a flag for indicating that radiobearers establishment is requested, wherein in the attach procedure, anATTACH REQUEST message is received from the UE, an ATTACH ACCEPT messageis transmitted to the UE, and an ATTACH COMPLETE message is receivedfrom the UE, wherein the ATTACH REQUEST message includes UE capabilityinformation for indicating support of the control plane CIoT EPSOptimisation and information for a request to use the control plane CIoTEPS Optimisation, and the ATTACH ACCEPT message includes networkcapability information for indicating support of the control plane CIoTEPS Optimisation, the network capability information for indicating thesupport of the control plane CIoT EPS Optimisation is used by the UE torecognize that use of the communication by use of the control plane CIoTEPS Optimisation is accepted, and after the second control message istransmitted, the communication by use of the radio bearers is performed.11. The communication method performed by the MME according to claim 10,wherein the second control message includes information on an EvolvedPacket System (EPS) bearer.
 12. The communication method performed bythe MME according to claim 10, wherein the communication by use of thecontrol plane CIoT EPS Optimisation is a communication of user datausing a communication path for transmitting and/or receiving a controlmessage, and is performed via the MME, the communication by use of theradio bearers is a communication of user data using a communication pathfor transmitting and/or receiving the user data.